I tried it with a few simple apps and the performance in very simplistic card-like games was ~20 fps on a very powerful PC.
The input lag was very noticable when dragging cards with the mouse, so the performance is very, very far from native.
Windows Subsystem for Android currently uses the same infrastructure for GPU virt as the Android Emulator (ie command stream encapsulation with gfxstream, virtio-gpu device).