ok so, this is a more complex answer than it seems xD
Futa was supposed to be in game at first, but it was left on the table. Because we animate everything by hand, adding futa in game is not a simple matter of switching models like a 3D game. Plus we feel like reusing animations would be cheap. And adding 30+ animations was a loooot of work for "no new game content" (game content vs porn content is a whole discussion on its own).
That being said, the male and female player is in the lore the same person changing sex. Are they trans? What are their favorite pronouns? Do they just like to jave boobs once in a while and that's it? All questions that are willingly left unanswered so that the player can make their headcanon for themselves.
We do have a futa centric game, Futas of Eden, which has a new demo that came out recently ^^