When they first Announced 'Mewthree' all I asked to myself was..."So Pokemon Scientists/Team Rocket didn't learn anything, previously from the ordeal that Mewtwo brought up"
Mewthree is prob like a lot of people stated a borderline fail and success. Either way. It's Mewtwo vs Mewtwo and Freezas love child, Mewthree. If it comes down to a fight of course.
In-game or movie/show wise