>>50502041>needing balls to catch a mewtwo... cringe1) Just tell it you exposed & destroyed/disbanded team rocket.
2) Explain they are bound to return under a different name or in another form & you'll need its help to do so again.
3)Vow to help it murder all of team rocket ex-members and any other poke gangs you find & will release all your pokemon
4) travel the world stopping gang violence & evil organizations with your living superweapon bff
5)profit
You'd probably be best friends for life & not ever have to throw a ball. Mewtwo is hyper intelligent they would be logical & reasonable given the chance to destroy its nemesis but eventually realize that's not the sole purpose to life.