There's a truly outstanding and ongoing point of reference for Rocket League Trading this precise sort of incorporation. Fortnite, which is as of now the best game on earth, joins progress through its own personal Epic Games account framework.

This permits players to purchase the Battle Pass in one spot and work toward new prizes over all stages. Rocket League could in all likelihood be attempting to copy this model.

(Provided that this is true, don't be astounded if Sony RL Prices will not take care of business - simply like how it won't let Fortnite players on PS4 utilize their Epic records on different stages.)