It's just gonna be a real letdown for me if it's true. From what we can tell, Ekko is the leader of the band based on him being front and center in all the art. Plus he hasn't gotten a non legacy skin since PROJECT Ekko.
Yasuo has so many skins and already has a legendary. But based on his sword sheath being on his back, he may have some animation changes and may be legendary :(.
Id rather there be no legendary skins than Yasuo get another really nice Legendary honestly.