How to apply motion blur to child component

I’ve a actor blueprint component that has a propeller as static mesh child component. I want to apply motion blur when propeller rotates because at high rotation speed it feels like slowed down to limited frame rate. I tried out several solution without desired effect including motion blurred propeller used in Platformer example. Finally I hit upon PostProcess component that I can add to my actor and somehow I can tell it to apply motion blur to actor’s child component. I have now these two issues:

  1. PostProcess component seems to work in editor and I can see effects but in actual game play I don’t see any effects. For debuuging I’m using effects like film tint.
  2. PostProcess component always applies effect to whole actor instead of specific child component.

Any idea how to use PostProcess component to solve above two issues?

Hi, may be too late, but you can fake it like in this video: