Just played Smash Ultimate at Best Buy. I got to play a few rounds. I played as Kirby, Pokemon Trainer and Link.
I haven't gotten the chance to try it, but I heard that Kirby can inhale and spit out items and projectiles like he can with characters. For his up taunt, he does a little pose that is super quick.
Charizard felt pretty much the same as in Smash 4, but he lost his Rock Smash down special. I'm gonna miss it! Ivysaur felt good, but I couldn't really get a grasp on Squirtle.
I will say that landing strong hits feels more impactful in this game. I got to play on Saffron City and Saw Porygon! I think Porygon has a new cry when it comes out the door. It sounds cuter and not as squaky and ear grating as in the original.
If you have any questions, I'll try to answer them the best I can.