I found an issue in UE5 Preview 2. Its easy to replicate, if you try and get a Player State from the Players Array that is found in the Game State (This is a build in Array of all player states in the game) the result is always not valid, even if the index is valid.
The player state is valid if you get it in the player character blueprint. So the state is valid. And if you use Find Item from the Players Array from the game state and plug in the Player State variable from the player character blueprint it find the correct index, but if you attempt to get that Player State from the Players Array using that found index the resulting Player State reference is not valid.
I have tested this in a totally new UE5 EA2 project and the problem still exists, the exact same code works correctly (Meaning it returns the correct valid Player State) in UE4.24 4.26 and even in the EA of 4.27.