If you’ve ever played Fortnite on PS4, you’ll be blocked from playing the newly-released Nintendo Switch version.
Playing Fortnite requires you to log into an Epic Games account. If you’ve already connected the account to a PSN ID, you will be greeted with the following message when booting the game on Switch (via Reddit):
“This Fortnite account is associated with a platform which does not allow it to operate on Switch. Neither the Fortnite website nor Epic Customer Service are able to change this. To play Fortnite on Switch, please create a new account.”
Source: Eurogamer Fortnite blocks you playing on Switch if you've already logged in on PS4