Save the file with CTRL+X, then Y, then enter. That saves the file.
Run in shellinabox.
Reboot the system.
Check that the noexec flag is no longer present for that particular mount.
Open shellinabox again.
Done. You should be able to transcode and access your Plex outside of your network.
Looking forward to trying this. I’ve always been able to access plex from the outside network but read somewhere hardware decoding isn’t possible. Will try it out (might breath new life into my proliant n40L).