"Sony’s cross-play function for PlayStation 4 has now completed its beta phase and is a full feature for developers to make use of.
Strangely, Sony has made no official announcement about cross-play being promoted to a full feature. The new instead comes from a Wired article, which states that cross-play is now available to any developer that wishes to implement it in their game. Call of Duty: Modern Warfare seems likely to be the first new game to support this at launch, with it being set for release later this month.
The beta phase of PS4 cross-play included games such as Fortnite and Rocket League, which helped prove the system’s capabilities. Hopefully from now on we’ll see many more multi-platform games support cross-play."
I wasn't even aware that there was a Beta phase for this.
I hope this means devs of online multiplayer games will make use of it. Monster Hunter: World comes to mind, but the PC version is still a few months behind, so that probably won't be possible.
~Edit~
Announcement trailer already from none other than Xbox.
Your squad just got a lot bigger 🍗🍗
— Xbox UK (@xboxuk) October 2, 2019
PLAYERUNKNOWN’S BATTLEGROUNDS cross-play with PlayStation is officially here ➡️ https://t.co/QAN2SssjG1 pic.twitter.com/rab2oTpYh6