The FailsafeArea of NavModifierVolume is generated at a different location from the center of the actor when it rotated. This means that the effect of rotation is incorrect. (see attached file)
1. Create a new Blueprint Actor.
2. Add StaticMeshComponent and assign Cube Mesh.
3. Add NavModifierVolume Component.
4. Set the StaticMeshComponent to "NoCollision".
5. Added NavMeshBoundsVolume to Level.
6. Add the created actor to Level.
7. Select actor in viewport and change "yaw".
Then, NullArea of NavModifierVolume is applied at a distance from center of the actor.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-92064 in the post.