>>31261409He's been calling it PM Gals even back when only Misty and May existed. My guess is he'll loosely follow the story of the anime where Serena goes off to Hoenn on her own for a while, whereas Ash goes to Alola.
Serena's already seen Ash fuck Misty/May/Dawn/Iris and Shauna in front of her, so she knows he does other girls even if she is his favorite.