If there is a Gen 8 Pokemon that gets into Smash Ultimate's Fighter Pass 2, the best choice is Cinderace.

-football player-style combat, only uses hands to grab, everything else is kicks, head, and body blows
-fast, agile, middle weight, good air speed
-large variety of moves to use: Zen Headbutt, Headbutt, Double-Edge, Bounce, Pyro Ball, Blaze Kick, Hi Jump Kick, Double Kick, Mega Kick, Mud Shot, Low Sweep, Iron Head, Acrobatics, Flame Charge
-Neutral B would be Pyro Ball, you can hold B to charge its power, knockback, speed, and duration as well as aim it. Sometimes it would be Gunk Shot, which splats on impact and poisons everyone who gets splatted, sometimes it's Mud Shot which splats and slows down everyone hit
-Neutral A can be Double Kick into Mega Kick
-Dash Attack can be one of the Headbutts, Double-Edge, or Flame Charge
-Side B can be Hi Jump Kick
-Up B can be Bounce, leap up in an arc and knock people out of the way, if you land on someone going down you damage them, bounce back up and send them down
-Down Smash can be Low Sweep
-Final Smash can be its new GigantiMax, and you aim the giant fireball at the stage then kick it, dealing massive damage and knockback at the impact site