I have a sizeable Plex library currently stored in 4 2.5" HDDs attached through a SATA hat to my Raspberry Pi 4. It served me well as a Plex server in the years since I've got it but I've recently outgrown the Pi and I'm about to move my small homelab to a Mini PC. I was wondering if it'd be a bad idea leaving the four disks attached to the Pi while moving my Plex server to the Mini PC, serving the files through SMB.
That'll work fine. The only thing that matters is the connection reliability and speed to read the media files.
I did the opposite, with Plex and the drive on the big rig and a pi running all the *arrs.