General comment:
Given your need to support 2 - 3 users, you may not need to worry about using hardware accelerated transcoding. It depends if you need to transcode 4K video.
Hopefully you and your users will be direct playing / direct streaming the video, which requires very little CPU processing power.
If you do need to transcode video, the Ryzen 3 3200G will transcode multiple 1080p video streams. See the What Kind of CPU do I need for my Server? support article.
The Ryzen 3200G CPU will not transcode 4K video, as a Passmark of 17000 is needed for 4K HDR video. If you’re running a Linux OS, you cannot take advantage of the GPU to assist with transcoding.
That is why I mentioned Intel. The i3 cannot transcode 4K HDR video on the CPU either. However, with hardware acceleration you can transcode it using the on-board graphics processor.
Caveat: I’m not a FreeNAS user. Others can will correct me if I’m providing incorrect or misleading info.
From what I can find, FreeNAS does not currently support hardware acceleration on any platform. It will support hardware acceleration in an upcoming release. See the below post. Note that the ixsystems thread mentions Intel, but not AMD or Nvidia GPUs.
