Yeah, but just in case
I don't think we have anything to worry about, the leaker's been right about everything so far including the 2nd Mewtwo mega evo.
Though there's always the chance Fennekin's mega evolution loses psychic type to become fighting. :3
Not 100% confirmed yet:
MegaMewtwo #2 is Psychic/Fighting with Steadfast ability, Mega Garchomp has Sand Force. Supposedly Mega Blaziken shown on a new anime poster.