I’m curious. This particular article doesn’t point out any particular issue with hardware-accelerated transcoding on Windows with Intel (except in the case where there’s an Nvidia GPU installed and in-use). Did you mean to quote a different article, or can you point to the info in this one which implies there’s a limitation?
As others have pointed out, the only documented limitation with Windows on Intel, as it pertains to hardware-accelerated transcoding, is with tone mapping; if you don’t need that specific feature you’re not likely to run into any Plex-imposed limitations currently. Hardware-accelerated decoding (via DXVA2) and encoding both work fine in this environment.
I’d just like to ensure we’re trying to answer the right question/solve the right problem here. (I don’t think that you’ve ever mentioned that you’re trying to play HDR media, though I could have missed that.)
For what it’s worth, server-side hardware-accelerated tone mapping is not necessarily needed in all cases. There are client devices which will perform this function as well.