How to use physics engine only, or skip rendering completely

is it possible to make UE skip the rendering completely , for all objects in the scene.
Everything else should still happen, animations, physics, just no drawing.
Ideally, I would like to switch rendering on/off via a button.

If this is not possible: is there a way to use just the physics engine alone?

I have googled and searched this forum, but I did not find a conclusive answer.