I created this method in unreal engine 4 using solely the blueprint system. I was able to achieve real-time reflection ( no SSR, no RTX), and fake global illumination at runtime and in the editor.
The system runs incredibly fast. This demo runs at 120 fps on a two generations old GTX 970, therefore it can also be implemented for VR solutions.
The fake GI isn't very flexible but the real-time reflection is and it's more suitable for making studio lighting setup and product renders.
I'm considering releasing this on the Unreal Marketplace if it meets the interest.