Yes.... Echo Racer.... since they decided to add in new characters but give them the same moveset in Smash Bros, I figure that Echo-Racers would be something that Nintendo would do.
It actually kinda peeves me that Dark Samus, Lucina, Daisy, Crom, Dark Pit, Ken, & Richter Belmont aren't their own characters that are just similar to some of the other characters.
I mean back in Brawl you had Fox, Falco, and Wolf being basically the same character BUT they had some variation between their move-set, damage output, speed, floating, and specials that they each were unique.
Take a look at Link even ! Young Link is smaller and faster than Link. And Toon Link is floatier and able to vault off walls. They each have nearly the same moveset with some variation to speed and specials.
But the Echo Fighters are just a model and audio change. Cosmetics in the form of another character. It would be like Samus being dressed in her Gravity Suit rather than her Varia Suit being made into a new character on the roster. Or adding James McCloud to the roster where his just a scruffier Fox McCloud with sunglasses and then saying "here is your new character. Same moves, different getup and audio effects."