Honestly I wish this was a thing. With & Knuckles being a mode in the game it'd be nice if characters could interact with Knuckles like they could with Tails. They did have characters ride Knuckles while gliding in Sonic Advance 3. Idk what they'd do with Sonic as a partner though. Hell him spawning back makes no sense when you select him, he just uses his peel out move (although it's odd that they assigned an animation to that at all, almost like they planned on us altering the game to enable whatever partner you wanted. Given their origins though I think they knew that would happen).