Star Trek's Everything You Need to Know About the Borg Queen states "Only one Queen exists at any given time".
But a recent episode
How do the Borg accept such a deviation from the norm? You'd think their minds exploded from their own paradox.
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Sign up to join this communityStar Trek's Everything You Need to Know About the Borg Queen states "Only one Queen exists at any given time".
But a recent episode
How do the Borg accept such a deviation from the norm? You'd think their minds exploded from their own paradox.
In the case of Picard, the reason is simple (and an explanation that is often encountered in contemporary motion fiction): "this Borg Queen was from an alternate timeline created by Q's manipulations and she merged with Doctor Agnes Jurati".1
Nevertheless, the idea of multiple, simultaneous Borg Queens has been suggested earlier, in the Destiny novel trilogy. From Memory Alpha (my emphasis):
In the Star Trek: Destiny trilogy, a newly installed Queen oversaw a massive Borg invasion of the Alpha Quadrant. It was later revealed that the Borg Queen was merely an avatar for the true power behind the Collective. The Destiny trilogy also mentioned that multiple Queens have been known to exist simultaneously in the Collective, but they all possessed the same agenda.
While these novels are not considered canon2 (Fandom even mentions how "Star Trek: Picard and Star Trek diverge significantly from the Destiny trilogy"), this notion of simultaneous Queens is obviously not new to Picard.
Wikipedia has a few more subtle remarks to add on the matter (my emphasis [and notes]):
Whether or not [the portrayals by different actresses] represent the same queen is never specified.
The queen appeared to be killed in both First Contact [1996] and "End Game" [2001], so there may be a total of three queens throughout the series. In First Contact, the Borg Queen is seen during a flashback of Picard's former assimilation, establishing she was present during the events of "Best of Both Worlds" [1990].
It is assumed the Queen can reincarnate, possibly into a clone, with their former memories; so, to some degree, these are the same avatars. There is no simultaneity here, but these incarnations are suggestive of change and individuality.
1: Source
2: Wikipedia Star Trek entry: "The Star Trek canon includes the Original Series, 11 spin-off television series, and a film franchise; further adaptations also exist in several media."