Character Movement Component does allow for custom movement modes. In fact you could possibly get this working by simply changing the movement to Flying which allows for rotation of the capsule component. Movement Mode (None) disables CMC for the most part.
You will have to write your own movement logic if you go this route though. There’s also walkable slope angle that you can adjust as needed in real-time.
Regardless the approach you will be disabling and enabling CMC depending on the capsules orientation in world space.