Say every legendary has to pick a 'chosen one' of their own. What picks who? Include non-godly legends like ultra beasts or the raidons if you want, I'm not a cop.

It occured to me while thinking this that Koraidon matches Nemona and Miraidon matches Penny.

Mewtwo matches with Giovanni a lot and maybe they would get along in the game universe as seen with RR, but I think Sabrina would be a good fit.