Me and my brother have just recently gotten the game when it was free on PS Plus. And then bought the DLCs, though several major issues have occurred in our time since then.
Encountered a bug with the game where suddenly you can’t interact with anything. Nothing works (can’t ride bikes, can’t pick up ammo, can’t open doors, can’t access inventory). It appears to be some sort of major desync because me and my brother just freeze on each other’s screens.
This has also occurred in multiplayer sessions with complete randoms. I’m currently running from a LAN line with Google Fiber. But sometimes it says that the host doesn’t exist or just gives up before it can even find a game.
Client-specific enemies: Several times through multiplayer they have encountered phantom enemies. Where only one person (is not exclusive to the client or player). They are fully active, deal damage, and when killed will drop loot for the person who can see and interact with them. They will attempt to attack other players within the session but cannot interact with those players themselves.
Dog Perma-death: The dog can oftentimes simultaneously become nonexistent and gain a great deal of damage to the point where they’re downed. But they exist nowhere on the map and after leaving the session. They then reappeared to be able to be revived and used again.
Update: Generator towers are also dependent on the player, to which it may be in the ground. To others, it’s fully risen and can be shot.