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

The 3 Promotional Avatars wearing Rain Boots / Wellies

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

Basically

Valgallah's Cream's "Chao Force" Super

Command is

D,DF,F X+Y

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

Yoshi and Birdo cosplaying as Ichigo Momomiya

Some Rain booted artwork of these characters i did

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

Sprite dump of V3 Fang + Evolution

The "Big Green Man" (Guest) teaser.