Help me fix some issues on my UE 4 project for Vtubing

Hi.. I have a UE4 (Unreal Engine 4.27 Mac version) project with two models. Issue to resolve are: 1) The coin has a weird white edge when turning on the side. 2) the head movements are incorrect (when I turn my head right or left on Live Link, the coin rotates left and right. When I tilt my head up and down the coin rotates up and down. 3) the Football model doesn't have the head movements at all in the code (copy head movement codes from coin model to football) 4) Set up my project so I can stream my UE4 model on Play mode to become a virtual webcam for OBS or Camtasia. using NDI ?