How to link Xbox and pc

I mainly played marvel rivals on my Xbox and have bought quite a bit of cosmetics, but recently I got a pc and wanted to play on there instead. I downloaded marvel rivals through steam and went into the game and logged in via a new account as I saw no option to sign in w an existing one on the log in menu. I created an alt account basically, assuming that I could swap accounts when I was in the game. Figured out I couldn’t do that so I googled some ways to help and ended up linking my Xbox account to my steam account but went back into marvel rivals on pc and my alt account was logged in and not my other. Is there any way I can get my pre existing Xbox account on my pc marvel rivals??