How would a gacha Smash bros game work?

Before you throw dirt at me for this question: Yes, I know how awful it sounds a Super Smash bros game with gacha mechanics (as in games like Fire Emblem Heroes or Genshin Impact), but the idea was stuck with me for a while, specially since Nintendo is going for the gacha treatment with most of its games.

With that said, how do you think it would work? Aside from gameplay aspects and the roster, thinking of how it could handle pulls, currency and other common aspects of a gacha game.

My idea is that we could get a new character each month or two, with its own pull. And in order to pull this character, you could use tickets (like in Ultimate) that you get from the shop or by completing challenges