I would say that if your deck doesn't need a lot of bench space, play 3 or 4 Lele. Otherwise, I would just have 2 and expect to play one during the game, either early game or late game.
Decks that would want to play Brigette early game would have 4 bench spots occupied very early. You might argue that you can always use the 5th spot for a second Lele late game. This is not always truth, however. For instance, Golisopod/Garbodor would probably prefer to have Tapu Koko promo to use as a pivot rather than a second Lele, but I guess the choice depends on the given circumstance.
