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

Father and Son love

Despite being Water (Or Mutated Chao) slime sounds

The 3 Promotional Avatars wearing Rain Boots / Wellies

Yoshi and Birdo cosplaying as Ichigo Momomiya

(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!

(Advance 1) Angel Island Zone.

Originally for Infinite Battle Now retooled

The "Big Green Man" (Guest) teaser.