Plugin Help Hypixel's Warlords HELP

Hello everyone. Well I've had this question for a time now. How did Hypixel manage to do this kind of "Citizens" NPC showing the available game classes. But with your onw skin! I mean, every player sees their own skin. Is there any plugin for that? Or a command for citizens so every player sees their own skin? I really dont know how to do it but I would love to for my server. I got a great idea for it.

Pleaseee I hope someone knows how to do it. Thanks