I think by the end of the season, Charizard will return to the Charific Valley, Ash's unova pokemon will head to Professor Oak's in Kanto, and maybe as we have a final episode where Iris has to say goodbye to Ash, Axew is sad much like Piplup was, and tries to run away with Scraggy. And then, a problem unfolds with some wild pokemon, and they both evolve simutaneously to protect it each other. Then they leave.
Aside from that, I can't really see anything else for it. Such a shame as it was a good pokemon, a good modern representation of Ash's Primeape in many ways.