Recently I saw a sword fighting film. The hero is a very very good sword fighter.
One of the heroes has a sword with a reversed blade. Later it is revealed it can be reversed.
Film is quite recent (later than 2011).
Is it perhaps Rurouni Kenshin from 2012?
Rurouni Kenshin (るろうに剣心 Rurōni Kenshin?) is a 2012 Japanese film adaptation of the manga of the same name originally written by Nobuhiro Watsuki. Directed by Keishi Ōtomo, the film stars Takeru Satoh and Emi Takei. The film focuses on fictional events that take place during the early Meiji period in Japan, telling the story of a wanderer named Himura Kenshin, formerly known as the assassin Hitokiri Battōsai. After participating in the Bakumatsu war, Kenshin wanders the countryside of Japan offering protection and aid to those in need as atonement for the murders he once committed as an assassin.
In 1868, after the end of the Bakumatsu war, the former assassin Kenshin Himura promises to defend those in need without killing. Kenshin wanders through Japan with a reverse-edged sword during the transition of the samurai age to the New Age.