MOTDRandomiser

MOTDRandomiser is a plugin that makes it so the MOTD of your Bukkit/Spigot/Paper/BungeeCord/Velocity server is randomised every time a user presses "Refresh" in the server list. (Plus, you don't have to restart your server to update the MOTD list!)

You can update the list of MOTDs in plugins/MOTDRandomiser/config.yml or plugins/motdrandomiser/config.yml depending on the server software. Once you've done that you can reload the file using /motdrandomiser reload.