Adding libraries from two different (local) servers

Maybe I'm wording it wrong, but I couldn't find anything on Google to help me with this problem.
I have my main Plex install on a TrueNAS server. I have a separate Synology NAS that I would like to start using as I have ran out of space on my primary NAS (TrueNAS). Both are on the same local network.
Am I able to add a folder from my Synology to the Plex instance running on my TrueNAS? Or will I need to have a Plex_01 and Plex_02?