This plugin allows you to make Holographic Displays, here are the features:
Create floating text lines!
Floating items!
Fast and easy to use.
Simple API for developers.
Transform images into holograms with a single command.
You can create your own animations!
Includes the animated rainbow color &u!
Supports any unicode symbol.
Can display the amount of players online in a BungeeCord server (supports RedisBungee)
https://dev.bukkit.org/projects/holographic-displays
(You might need this plugin to run other plugins like Chat Bubbles)