What is PS4 crossplay and what games use it?

Now that Sony says any PS4 game can use crossplay what titles are actually taking advantage of it and how does it work?

Top 5 Multiplayer Games That Support CrossPlay - PC/PS4/PS5/Xbox One/Xbox Series X/S - MySmartPrice

All cross-platform games (PS5, Xbox Series X, Switch, PC, and more)

All PS4 Crossplay Games - A Complete List Of Games You Can Play With Other Consoles In 2022 - PlayStation Universe

How to Fortnite cross-play on PS4, Xbox One, PC, Switch, iOS, and Android

These are the best PC and PS4 crossplay games

What is PS4 crossplay and what games use it?

26 Cross-Platform (PS, Xbox, PC, Switch) Games to Try Today - Geekflare

THE 16 Best Crossplay Games to Play Right Now 2023

Gaijin: Most if Not All Devs Are Ready to Enable Full Cross-Play; Voice Chat Should Also Be Supported on All Platforms

Sony really hated PS4 crossplay, confidential documents reveal - The Verge

Best Free Cross Platform Games on PC/PS5/Xbox/Switch in 2023 - MiniTool Partition Wizard