Unlikely. How many non lewd fan games are there out there? Fan games that do Pokemon way better than Game Freak could ever do? A lot. Moemon is also a thing. None of them are getting sued. I doubt a niche sex game is going to be the one that gets ended.
There's literally fan Pokemon MMO's. Besides, if anything this is a complete parody, the girls look nothing like Pokemon with only vague name references. Nintendo doesn't own turn based battles. Tem Tem, Nexomon, and more are going fine without being sued.
