RequireLinked4Gameplay
1.2.0Require players to link their accounts to Discord or require users to have a subscriber role
RequireLinked4Gameplay is an addon plugin for DiscordSRV that will let you require your players to link their Minecraft accounts to their Discord accounts in order for them to be able to connect to the server.
Optionally, you can also require them to have a specific role on your Discord server such as a Twitch or Patreon subscriber role.
Since this is a DiscordSRV addon, you need DiscordSRV installed as well.
Screenshots: 
Yes, both of these messages are customizable in the config.
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