I was having the same issue, tried restarting everything, I finally got it to work, if you disable crossplay, click multi-player, let it do the load screen, then re-enable crossplay and hit multi-player again, this time while it's in the load screen I had it load my Xbox account on another window, I originally hit the "let's go" button, and it still wouldn't work, I had to choose to use a different account, then once I logged in it kicked me to the start screen, I was able to load in and do multi-player fine, after that I was also able to choose my original account, log in with it and now it will let me access multi-player, hope this helps!
