Hey there @Ozgalis! Welcome back to the community! You went through most of the early troubleshooting I was going to bring here, so I think the best move would be to determine everything that could be influencing this.
Are you using any other scripts that touch the player character in any way?
You mentioned you already checked the project gamemode and the world overrides so I won’t bother you on that.
Your gamemode doesn’t have any spawning logic?
Are there any other pawns with auto possess in the level?
In your gamemode, are you spawning as a spectator?
Start the game in viewport, hit F8 and check your outliner (and visually), does your correct player spawn in the correct location?
Put some prints behind the player’s inputs to see if they are reading at all. Also put them in the player controller to test.