this may or may not help @ Plex, 4k, transcoding, and you - aka the rules of 4k - a FAQ
first thing is, if you need to confirm that your content is direct playing or not.
you can monitor your streams @ https://app.plex.tv/desktop > status > dashboard
If you are transcoding 4k, then that means your tv clients cannot direct play it.
if you are streaming to smart tv apps, then most likely the problem is the HD audio is not compatible, and/or you if you have subtitles enabled that can cause transcoding as well.
if your content is direct playing, that is good, but it means that its probably your network that can’t keep up and you need to figure out where the bottleneck(s) are and fix or remove them.
