Well FE Warriors isn't as financially sound as even Hyrule Warriors. Though, I'd much rather have that than Hyrule Warriors.

Street Fighter is a traditional 2D fighter. Super Smash Bros is a brawler. 

yes please!

well brawler and fighter are interchangeable for me but yeah that's obviously what I meant

That sounds really interesting. Buy I doubt that could happen... most probably a Nintendo vs Bandai game...

Lol, I started a thread about a year ago with this very same idea. I had worked on it for almost two hours, had a long ass essay on how and why this would work, had graphics and everything. Then when I was wrapping it up, my browser crashed and I lost it.

So obviously, I concur with everything you said. The biggest argument against it I see people make are, "But Nintendo characters are short! How would you do Mario vs. Ryu?" Admittedly, I haven't seen anyone say that in years, but TvC showed how it would work with characters of all sizes, and both Capcom and Nintendo have tons of chibi-sized characters and regular human proportioned characters to make it all work.

And if you think about it, a lot of groundwork has already been laid by both companies. You could copy-paste a ton of moves and combos from SSB and tweak them to work in a TvC style format. Mario, for instance, is clearly a shotaclone (Ryu clone):

Uppercut = Shouryuken/Dragon Punch

Fireball = Hadouken/Fireball

Tornado Spin = Tatsumaki Jiten/Hurricane Kick

FLUDD = Donkey Kick

You got your slow bruiser with no projectiles in DK who would matchup against Zangief/Alex/Haggar, your agile female who controls the air in Samus would matchup against Chun Li, and so on. This game needs to happen.

I'd be down!

Why can't it happen?

I think now is when it could happen the most for the reasons I stated. As far as I know, only Capcom makes Vs. Games. No one makes cross-company (X company vs Y company) fighting games without Capcom, so that's much less likely. 

Would be cray cray