Rocket League Trading into the game with a Xbox. from xingwang's blog

whether you sign Rocket League Trading into the game with a Xbox. 

Other tradable things will be tradable paying little heed to which stage you previously got them, yet you'll just have the option to start exchanges with players that are signed into a similar stage as you. In the event that you'd prefer to exchange a thing to a companion on a Xbox as a PC player, you'll either have to change to a Xbox yourself or have them sign into the game through a PC.Trading cross-stage on Rocket League will expect you to approach various gaming stages. In the event that you'd prefer to exchange with a player on Nintendo Switch, you'll need to sign into the game from one yourself or welcome them for an exchange when they're playing on your favored stage. 

At the point when you have the "play on a similar stage" box checked, you can welcome them to your gathering in Rocket League. When they acknowledge, select their name or vehicle and pick "Welcome to www.lolga.com Trade."