There’s no need to give a direct answer to this question, really. For starters, Super Smash Bros is a game that’s already several iterations old. The different iterations brought incremental changes and now form a series of fighting games that left an imprint on several generations of gamers.
On the other hand, Multiversus is a similar game. But, it sports different game mechanics, has a different art style (arguable), and most importantly – it’s not even a full game yet. We just can’t do concrete comparisons of these two… at least not yet.