Ok. I read it to mean change the file name in just the m3u file.

@simongeoghegan As long as you take a backup of the .srm you needn't worry about anything. The network share is the easiest and it only shares user data folders for retropie like: roms bios and configs. The folder will be displayed like a windows directory in explorer, the local network doesn't need any configuration, it could be either through a router or directly connected through the ethernet.