I don’t really know if this would work in practice, but maybe something like:
- Create a Rotator Variable
- On Begin Play, get the world rotation of the mesh your player is sitting in and save it into the variable
- On Tick, get the world rotation of the mesh your player it sitting in, subtract it from the saved variable, and apply the result as a rotation offset to your pawn camera. Update the variable again with the current rotation.
Technically that should add the mesh’s rotation to your camera every frame but I don’t really have the setup to try this right now so I can’t guarantee anything 
Edit: or mirsabayu’s suggestion would be a lot simpler if it works.