https://www.techradar.com/news/sony-finally-enables-fortnite-cross-play-for-ps4

PS4 users playing Fortnite will soon be able to play seamlessly across their PS4 and non-Sony consoles, as well as play with friends who use different consoles, according to a post on the Sony PlayStation blog.

This is a big and surprising move given that Sony has been vocal about not allowing cross-platform play for Fortnite players across multiple consoles in recent months.