The only plugin you need for Custom Join Messages, works with minimessages formatting (No Hover or Click Events) and default colour codes.
Each player can get a custom message from their UUID, an example is in the config.
If you are using VanishNoPacket or SuperVanish it wont sent messages when they join, sadly if you are using SuperVanish anyone that can vanish cannot have a custom message as it will use the default SuperVanish message.
Support: - Contact me on discord at: ebic#5512