League anime will most likely, turn into a horrible series of cluster F's. So I am not entirely with the idea.
Because there is nothing to support anybody from behind, and there is barely any connections between the giant character roster (besides the friend/foe relationship there is pretty much nothing), there is no motive and there is 0 explanation. And the original lore/set - up got recton'ed.
If someone wish to attempt some large scale series where it involves a big world with many, many characters. You either need to follow the One Piece model where all the characters' story are connected in one way or another even though they may not notice it, and a very large relationship grid already pre-made ages before things get slowly revealed through meeting plot crucial characters or triggering flashbacks.
Or at least use the traditional DBZ style where it continuously introduces more powerful and more ridiculous power creep to gradually include more and more characters into the show.
Otherwise I don't see how the series would work in general tbh.