If he does, I hope some of it is fan service. Like Ash catching Larvitar, Spoink, and Hippopatas
If Ash were to catch one thing from each region as he travels through them what would you want them to be?
I don't want him to get anything from Kanto (from there I want him to get at least Pidgeot and Primeape back and say hi to Butterfree and Lapras) he's got a dozen Kanto Pokemon already not counting the extra Tauros, but if he has to get something maybe let him actually catch the Gastly line this time?
Johto: Larvitar (maybe he's a Tyranitar now?), Houndour, Espeon,
Hoenn: Spoink (maybe a Grumpig now?), Flygon,
Sinnoh: Lucario, Hippopotas
Unova: Not sure he got a lot in Unova too. Maybe, Venipede?
Kalos: He gets Greninja and Goodra back (at least the frog), maybe a Tyrunt (because T-REX!)
Alola: Passimian