This is an issue I've experienced for a while, and I'm no longer sure if it's being caused by a mod or is an issue with default AKI. Whenever I enter a raid as a Player Scav, the first person model is different from the model shown in the main menu and in the entering raid loading screen. Attempting to view your third person model in the "Overview" tab of the player's inventory menu causes the model to fail to load, and for the player's menu to lockup and become stuck on that tab. Attempting to change tabs does nothing, as does exiting and reentering your inventory. You can force the tab to change to the "Inventory" tab by searching a container, but the rest of the tabs remain locked up and inaccessible. This behavior persists after the raid ends for both the Player PMC and the Player Scav, and affects the main menu version of the player's inventory/stash menu. Restarting the game resets this behavior.
I've also noticed that whenever I open my inventory for the first time after entering a raid as a Player Scav, it always starts on the "Tasks" tab. Additionally, sometimes the first Player Scav I use after starting AKI isn't affected by this lockup bug, but this is very inconsistent and seems almost random.