>>47039472>harnessNo one IIRC, a pokeball limits their power, so except for the rainbow rocket leaders(though they do use master balls so maybe they caught them after using them to win), they usually can't.
Going into gameplay territory, a few battle frontier brains have legendaries and so do Faulkner, Winona and Sabrina in a DLC PWT challenge. Plus the widely known Trevor quote.
Then, starting from Gen 3 every battle tower-like facility has trainers using all non-680 legendaries available at the time, with the exceptions
-Lake trio was only in the battle tree
-All Gen7 legends are not in battle tree
-SWSH's tower, due the dexcut, only has Silvally
Then the player characters have a few canon catches.
I had an exhaustive list for each case but I can't find it so its mostly from the top of my head.