Barrel Roll Distortion

So I am making a VR app almost literally from scratch.

I have made my stereo display and my controls. I have made basically everything I need to do but after making a PostProcessing Material that performs a Barrel Roll distortion, I have learned that Unreal does not support that on Android.

I tried doing it through a refraction material which would always be in front of the camera but I also learned that Unreal does not support refraction on mobile either.

How can I achieve this effect on mobile phones? All I want to do is apply a barrel roll distortion to the image that gets drawn on screen. Is there an easy solution to this?

Thanks for your help!

Nick