What do you mean by "gender locked"? The option to play as FMC has been there for about 5 years now. If you mean the game doesn't take in consideration the character's gender otherwise, yeah, MMC and FMC are exactly the same the only difference being the pronouns and genitals in the text (and the mannequin in equipment view). Plus the occasional pronoun slip up and whatnot as it seems nobody bug tests as FMC.