Looking at the source code, it supports
1) Raspberry Pi MMAL
2) NVidia CuVid
3) Intel QuickSync
My system should support QuickSync, but according to this, you need to have your build environment set up properly with some Intel components to get this support in libavcodec. I'm pretty sure mine is not set up properly to build it and I'm going to guess the official cross-platform build isn't either. https://trac.ffmpeg.org/wiki/HWAccelIntro
I suspect we aren't seeing a lot of attention on this since most folks running windows are running semi-modern CPUs that can handle decoding the typical emulation 640x480 videos without breaking a sweat. It's a more critical piece for Raspberry Pi or linux users who might be re-purposing old hardware.
Don't know about the NVidia option. I ran with a NVidia card in my cab for a hot second until I realized it offered no real improvement, not even with HLSL shaders running.
Might be interesting to try throwing in support for Direct3D11 and/or DXVA2 options to see if they show up, which would work more generically on a Windows machine.