You want to put the prefix from your luckPerms group in front of your player name right? Normally you could add a variable to the corresponding Tag in the CustomTags.yml, but there is no variable at the moment to get the luckPerms prefix. I will expand the luckPerms variable catalog in the next update with a variable for the friendly name and displayname of the users group. I am sry that I can't give you a direct solution at the moment. EDIT: It should be possible to add a variable for prefix & suffix in the next update.