How to let temporal AA settle down when pausing game?

I have animating semi translucent object that is looking very bad in temporal AA. In simulation mode(SIE), if I pause it, the AA will settle down in 2 or 3 seconds and everything will be looking very good.

but In play mode(PIE), if i pause(toolbar pause button), the AA will also freeze, not settling down. How can I make it behave like SIE?

The reason is that I am doing non real-time animation render using sequencer, and I want to use third party screen capturer to capture every frame in UE4. Sequencer render output is unusable because the realtime temporal AA is terrible for my object. FXAA is not a choice because it’s even more terrible.

I would like to screen capture it in SIE but unfortunately the view does not move along with the animated camera.

Any help?