Dying Light 2 cross-gen co-op support is confusing. Here is whether or not PS4 can play with PS5 and also whether Xbox Series X|S can play with Xbox One.
Is Dying Light 2 Cross-Platform? (PC, PS5, XBOX)
Is there crossgen in dying light 2? : r/dyinglight
Dying Light 2 Does Not Feature Crossplay or Cross-Gen Support
Dying Light 2 Cross-Play: PS4, Xbox One And PC Cross Platform Play Details
So, is it crossplatform or not? : r/dyinglight
Is Dying Light 2 Cross Platform? Understanding Multi-Platform Playability
Dying Light 2 Won't Feature Crossplay, Cross-Gen Not Available at Launch, Story Can Be Completed With Up to 4 Players : r/PS5
Dying Light 2 Cross-Gen Co-Op: Can PS4 play with PS5? Can Xbox Series play with One? - GameRevolution
Is Dying Light 2 Cross Platform? (PS5, Xbox, PC)