CustomName

This is a POC plugin that allows plugins to register custom names on top of entities. These entities are fully client side, and correctly sync between players.

CustomNameManager customNameManager = JavaPlugin.getPlugin(CustomNamePlugin.class).getCustomNameManager();

CustomName name = this.customNameManager.forEntity(player);
name.setName(MiniMessage.miniMessage().deserialize("<rainbow>%s</rainbow>".formatted(event.getPlayer().getName())));

For more information on the implementation details, see this gist.