>>37911295Not even close.
It's been speed creeped to the point that it has to run Timid or Jolly, or else it just gets killed by Necrozma or Marshadow, neither form can do anything whatsoever to stop a Xerneas or P-Don sweep, Mega Mewtwo Y just melts to priority, and both of them just die if something has a scarf, psychic is an absolutely worthless type in Ubers, and Fighting hurts more than it helps, especially since Mewtwo X wants to be more bulky, it can't hold a real item, so it's lousy as a wallbreaker, Necrozma, Naganedel, and P-Don are a better setup sweepers since they can boost speed too.
As far as megas go, Mega-mom, Mega-chicken, and Mega-Gengar all have much better defined niches, because Mewtwo just succeeds only at being mediocre.
Scarf Kyurem-White is unironically better than Mewtwo Y in any conceivable circumstance, and any possible niche Mewtwo X had got taken by Marshadow.
Mewtwo gets to hang out with the likes of Palkia, Reshiram, and Solgaleo in the irrelevant to Ubers, but still too strong (maybe?) for OU tier.
