Make sure you use the same Epic Games account on both Xbox and PC
Open Rocket League on Xbox
Go to the main menu and select Settings
Open the Extras tab
Select Account Linking
Sign in to your Epic Games account if prompted
Confirm your Xbox account is linked to Epic Games
On your PC, install and open the Epic Games Launcher
Sign in with the same Epic Games account linked to your Xbox
Install Rocket League on PC through the Epic Games Launcher
Launch Rocket League on PC
Verify your progress, inventory, and presets are synced
If needed, check your linked accounts on the Epic Games account connections page
Ensure Xbox is listed as connected under linked accounts