The 3 Promotional Avatars wearing Rain Boots / Wellies

The "Big Green Man" (Guest) teaser.

2/3 of them are references to

Sonic's Concept and is also a Skin in Sonic Superstars Cream's Debut (Though inconsistent looks)

A former 90s rival's (A red capped plumber guy) recent 3D platformer since 2017

Act Music as Rounds? (may not apply to every stage)

(Advance 1) Angel Island Zone.

Originally for Infinite Battle Now retooled

Basically

Valgallah's Cream's "Chao Force" Super

Command is

D,DF,F X+Y

Father and Son love

(coming some time soon or something.) The 1st Sonic Battle Redux arcade Run: Sonic.

Early previews of "Shining Wine (Not alcohol)" and "Castle Party"

I'm taking you down like its 1998/1999!