Dying Light 2 will have free cross-gen upgrades for PS5 and Xbox Series X

techradar.com:

Dying Light 2 developer, Techland, has confirmed that those who purchase last-gen versions of the game will be entitled to free upgrades to the current-gen versions.

That means that PlayStation players who purchase the game on PS4 will be able to upgrade to the PS5 version at no extra cost. When it comes to Xbox, Dying Light 2 supports the system’s Smart Delivery feature so Xbox One players will also be able to access it on Xbox Series X/S without having to pay anything more. 

Touching on the game’s co-op, Techland has confirmed that, with the exception of the prologue, players will be able to play the game from start to finish, including the epilogue, in co-op mode.

However, cross-gen and cross-platform co-op will not be available on consoles at launch. Cross-play will, at least, be available on PC across Steam and the Epic Games Store. 

The wording “at launch” does seem to suggest that cross-play could come to console down the line. Techland has already stated its commitment to at least 5 years of post-launch support so that doesn’t seem impossible but it's not been explicitly detailed.

Except the Prologue part, you'll be able to play AND finish Dying Light 2 Stay Human in the co-op mode! And yes, we do mean including the Epilogue