The Heartless design in Toy Story world is likely a homage to Geno. It's too on-the-nose to not be.
Also, I know I say I want Sora in the base roster, but I would
love for him to use his Kingdom Hearts 3 design and have a moveset based off of the Command Gauge and Keyblade Transformations, which he'd have to be DLC to properly incorporate imo. There's so much potential for a fun character there.
That's what I like about Sora. Regardless of which one Sakurai and his team decide to use he'll likely be super fun to play as.
I'd imagine a dual trailer for Sora and Geno would start with Yoshi going flying towards the screen, as the camera shifts perspective to see him flying past Mario, who's hunched over and shows damage from a long battle. Camera pans to in front of Mario where we see a shadow point their arm at Mario and charge up an attack: the glow of the projectile reveals it's a possessed, shadowy Geno ("
Geno(?) shoots for the stars!). He launches it as Mario, who braces for impact, only for someone to jump in front of Mario and slice it in half. He turns around and offers a hand to Mario, "Can you stand?" He pulls Mario up and turns back around to face Geno, "Let's do this. Together!" (
Sora lights the way!). Commence Gameplay. Geno fights good guys and Sora fights bad guys. Trailer ends with Mario getting a good hit on Geno, sending him to the ground. Sora shoots a Keyblade beam at him and purifies him. Geno gets back up and vigorously apologizes to Mario and Sora.
A Sora solo trailer is easy. Take this:
And make it about Smash Bros. Simple and Clean.