I was planning to set transcoding on the M.2 by using a Pi M.2 Hat board. However, since the M.2 is already there, should I just use it to run the OS and downloads, too, or just use it as a transcoding consumable and media drive? This Pi 5 has 16Gb of RAM, so it might handle every bit of the transcoding regardless, but I have not tested it. I'm also concerned about latency between the main Pi board and the hat, connected with a flexible circuit board cable.

Also, anyone have issues with media storage on external drive when using Plex/media servers?

Equipment has been ordered but has not been delivered yet. Should come the next few days.