What's the best way to get output(transform feedback) from the vertex shader?

Hi guys, so I’ve been using my own engine quite a bit lately and I’ve gotten used to using the power of the GPU, using vertex output, to do performance critical tasks. I can’t use Compute shaders, as I’m targeting older devices.

Anyone know how I can best achieve this in Unreal? I’d rather not spend a significant time modifying the engine.