It's funny you say that; One game, Sonic Battle, uses the same type of controls Smash does, or well, really similar. It's all "single button" for an action, depending slightly how you move the D-Pad or if you're in the Air. It's far more simple, mind you, but it's kind of neat. It's a GBA game, so less buttons overall.
Overall, there's a Walk, Run, Jump, Double Jump, Shield, Heal, 1st Attack, 2nd Attack, 3rd Attack, Heavy Attack(basically a combo finisher), Upper Attack(Just sends them into the air), Dash Attack, Air Attack(a normal attack while in the Air), Aim Attack(a move you use strictly after the Heavy Attack, pursuing the opponent), 6 Specials that are Ground or Air(Shot, Power, Trap) and a "Style". That's not counting mechanics like their Attack power, Defense power(called Strength), Special ability(think like Mewtwo floatiness), and 3 Colors. That's not counting the unique moves only Emerl can use, all "hidden" moves, if you will. ??? moves(more or less Final Smashes ideally), Combo Cards(basically preset combination moves), and Ultimate Attacks(see all those list of attacks? Walk through Style? Those all have Ultimate versions that are ideally better than normal cards. Think Meta Knight on crack).
The game itself is very easy to play and access, but the story mode isn't nearly as fruitful due to repetitiveness, a poor RNG, and a lot of random difficulty. On the other hand, the actual story and dialogue is great(outside of typos). Funny too.
I think that is probably one of the best Fighting games I've played that took a bit after SSB. I should note it lacks Items, so it's closer to a Technical Fighter(also has HP and a meter that builds up that can let you do a OHKO with your Special attack). I hope what I said isn't that confusing, but the summary was a bit weird to type.