Translating between languages is difficult, including whether to modify the gender of words that are translated.
In the English language, the original language of the movie Captain Marvel, many titles of jobs and ranks have a single non gendered form, even though those jobs and ranks may have been originally used only by males.
There are many other titles in English which have both masculine and feminine forms. However, the masculine form is usually used for the holder of the title, assumed to be male, and the feminine form for the consort or spouse of the holder of the title, assumed to be female.
As females in the English speaking world became more and more equal in job opportunities to males and enter into roles previously occupied only by males, they usually continue to use the previously all male titles of the job instead of feminine forms of those titles.
In the United States military there are no female forms of ranks. Thus the wife of a General John Smith would not be called Generalissa Smith but Mrs. John Smith or Mrs. General Smith. And a female general named Joan smith is not called Generalissa Smith, but General Smith or General Joan Smith.
In the English language the title of captain is non gendered, traditionally used only by males but increasingly by females, and has no feminine equivalent, which would be used only by the spouse of a captain anyway and not by a female captain.
The original comic book Captain Marvel (1939-1953 and 1972-present) was a Superman-like superhero that Billy Batson could change into by saying "Shazam", and was renamed Shazam in 2011.
In comics by Marvel Comics Captain Marvel was the superhero name of characters:
1) Mar-Vell, a male Kree (1967-1982)
2) female Human Monica Rambeau (1982-1996) who later used the names Photon, Pulsar, & Spectrum,
3) male Kree-Titanian hybrid Genis-Vell (1995-2005) who also used the names Legacy and Photon,
5) female Titanian/Kree hybrid Phyla-Vell, also known as Quasar and Martyr,
6) male Skrull Khn'nr (2007)
7) male Kree Noh-Var, also known as Noh-Var and Protector
8) female Huaman/Kree hybrid Carol Danvers (2012-present), previously known as Ms. Marvel, Binary, & Warbird.
So the title of Captain Marvel has been used by both males and females of several species without gender modification.
And those are facts which the translators may have considered when deciding how to translate Captain Marvel into Portuguese.
And historically there are examples of females using the same titles as males without gender modification, going back thousands of years.
There were a few female monarchs in ancient Egypt, the most famous being Hatshepsut who ruled from c. 1478-c.1458 BC.
In Egyptian history, there was no word for a "queen regnant" as in contemporary history, "king" being the ancient Egyptian title regardless of gender, and by the time of her reign, pharaoh had become the name for the ruler. Hatshepsut is not unique, however, in taking the title of king. Sobekneferu, ruling six dynasties prior to Hatshepsut, also did so when she ruled Egypt.
The title of the Chinese monarch was Huang ti or Huangdi, roughly translated as "emperor". The main wife of the "emperor" had the title of Huanghow.
Wu Zetian (624-705) the main wife of Tang Gaozong, became the de facto ruler of Tang Dynasty China from 660 to 690. Wu Zetian deposed her son the emperor in 690 and made herself Huangdi, founding the short lived Zhou Dynasty of 690 to 705 (not to be confused with other Zhou dynasties). Wu Zetian ws the only female Huangdi in 2,000 years, so her title of Huangdi is sometimes translated into English as "Emperor" and "Sometimes as "Empress Regent". Deciding on the proper translation of the title of Wu Zetian is made harder because Huangdi has grammatically indeterminate gender.
In the eastern Roman or "Byzantine" empire the Latin titles of the emperor were gradually replaced by Greek ones. By abut 700 the usual title was Basileus.
Irene Sarantapechaina (c. 752-803) married Leo IV in 768. When Leo ruled Irene was empress consort or basilissa. When Leo died in 780 Irene became the regent for her young son Constantine VI (771-before 805). When Constantine grew up he competed for power with Irene. Irene deposed and blinded Constantine VI in 787, ruling until deposed in 802. Meanwhile, Charlemagne was crowned emperor in Rome in 800, claiming the imperial throne was vacant since a woman couldn't rule.
Although it is often asserted that, as monarch, Irene called herself "basileus" (βασιλεύς), 'emperor', rather than "basilissa" (βασίλισσα), 'empress', in fact there are only three instances where it is known that she used the title "basileus": two legal documents in which she signed herself as "Emperor of the Romans" and a gold coin of hers found in Sicily bearing the title of "basileus". In relation to the coin, the lettering is of poor quality and the attribution to Irene may be problematic. She used the title "basilissa" in all other documents, coins, and seals.2
When emperor Constantine VIII died in 1028 he had three surviving daughters, Eudokia, Zoe (c. 978-1050), and Theodora (980-1056). Zoe married three men who ruled as emperors, and Zoe herself reigned as sovereign in 1042. Her sister Theodora was co sovereign in 1042 and Theodora both ruled and reigned in 1055-1006. Zoe would have used the title Basilissa when her husbands ruled the empire but I am not certain whether Zoe and Theodore used the title of basilissa or Basileus when they ruled.
However, Theodora preempted their plans when, despite her advanced age, she vigorously asserted her right to rule. She came out of retirement and convened the Senate, and the imperial guard proclaimed her "emperor" shortly before Constantine's death.8:596
Imperatrix is the Latin female form of imperator or emperor.
The term imperatrix seems not to have been used in Ancient Rome to indicate the consort of an imperator or later of an Emperor. In the early years of the Roman Empire there was no standard title or honorific for the Emperor's wife, even the "Augusta" honorific was rather exceptionally granted, and not exclusively to wives of living emperors.
It is not clear when the feminine form of the Latin term imperator originated or was used for the first time. It usually indicates a reigning monarch, and is thus used in the Latin version of titles of modern reigning Empresses.
Theophanu (c. 955-990), a princess or lady of uncertain ancestry from the Eastern Roman or "Byzantine" Empire, married Holy Roman Emperor Otto II. After Otto II died she was regent for their son Otto III and it is said sometimes used the title of Imperator.
It is said that when King Louis of Hungary and Poland died in 1382 his daughter Mary became king of Hungary and his daughter Hedwig became King of Poland, because the laws in those countries didn't mention the possibility of a queen regnant.
Louis the Great died on 10 September 1382. Cardinal Demetrius, Archbishop of Esztergom, crowned Mary "king" with the Holy Crown of Hungary in Székesfehérvár on 17 September, a day after her father's burial.1 Mary's title and her rapid coronation in the absence of her fiancé, Sigismund, show that her mother and her mother's supporters wanted to emphasize Mary's role as monarch and to postpone or even hinder Sigismund's coronation.
But this site gives her Latin title as:
Maria Dei gracia Hungarie, Dalmacie, Croacie, Rame, Seruie, Gallicie, Lodomerie, Cumanie, Bulgarieque Regina,
Princeps Salernitana et
Honoris Montis Sancti Angeli Domina
translated into English as:
King of Hungary, Dalmatia, Croatia, Rama, Serbia, Galicia, Lodomeria, Cumania, Bulgaria;
Prince of Salerno;
Lord of Monte Sant' Angelo;
The Latin titles regina and domina mean queen and lady, but the site translates them as king and lord.
Mary's sister Hedwig or Jadwiga became monarch of Poland:
The interregnum that followed Louis's death and caused such internal strife came to an end with Jadwiga's arrival in Poland. A large crowd of clerics, noblemen and burghers gathered at Kraków "to greet her with a display of affection", according to the 15th-century Polish historian, Jan Długosz. Nobody protested when Archbishop Bodzanta crowned her on 16 October 1384. According to traditional scholary consensus, Jadwiga was crowned "king". Thereby, as Robert W. Knoll proposes, the Polish lords prevented her eventual spouse from adopting the same title without their consent. Stephen C. Rowell, who says that sources that contradict the traditional view outnumber those verifying it, suggests that sporadic contemporaneous references to Jadwiga as "king" only reflect that she was not a queen consort, but a queen regnant.
In Poland Hedwig's Latin title was:
Nos Heduigis dei gracia Regina Polonie,
necnon terrarum Cracouie, Sandomirie, Syradie, Lancicie, Cuyauie, Pomeranieque domina et heres
Translated into English as:
King of Poland;
Hereditary Lord of the Lands of Crakow, Sandomierz, Sieradz, Łęczyca, Kujawy, Pomerania;
And again the Latin titles regina and domina mean queen and lady, but the site translates them as king and lord.
See also here: https://www.reddit.com/r/AskHistorians/comments/77es5c/why_was_jadwiga_of_poland_crowned_as_king_despite/10
And so I am uncertain how much Mary and Jadwiga were called kings and how much they were called queens.
I have read of other female kings of Hungary and Poland.
Empress Consort Maria Theresa, Queen of Hungary and Bohemia from 1740 to 1780, may have used the title of King.
Contrary to all expectations, a significant amount of support for the young Queen came from Hungary. Her coronation as Queen of Hungary took place in St. Martin's Cathedral, Pressburg, on 25 June 1741. She had spent months honing the equestrian skills necessary for the ceremony and negotiating with the Diet. To appease those who considered her gender to be a serious obstacle, Maria Theresa assumed masculine titles. Thus, in nomenclature, Maria Theresa was archduke and king; normally, however, she was styled as queen.
Her Latin title is given as:
Nos Maria Theresia, divina favente elementia Romanorum imperatrix, ac
Hungariae, Bohemiae, Dalmatiae, Croatiae, Sclavoniae, Ramae, Serviae, Gallitiae, Lodomeriae, Cumaniae, Bulgariaeque etc. regina;
dux Burgundiae, Brabantiae, superioris et inferioris Silesiae, Mediolani, Styriae, Carinthiae, Carnioliae, Mantuae, Parmae, Placentiae, Limburgiae, Lucemburgae, Geldriae, Wurthembergae;
marchio sacri Romani imperii, Burgoviae, Moraviae, superioris et inferioris Lusatiae;
comes Habspurgi, Flandriae, Tyrolis, Ferretis, Kyburgi, Goritiae, Gradiscae, et Arthesiae;
domina marchiae Sclavonicae, Portus Naouis, Salinarum et Meehliniae etc. etc.
The Latin title uses the feminine form of several titles and also masculine or neutral forms for other titles. The English translation uses the masculine forms.