1.) v5.03
2.) Spigot 2148 (1.13.2) - Don't know if its correct, but it's what my hosting provider says so...
3.) When going to a different world, I don't recieve the item (using PerWorldInventories), is there a way to make it work? If so, how do I do that?
4.) Everything in the config works, just wondering if I have to add something for my item. https://pastebin.com/ZMeu3XBV I wan't to recieve the item when I enter "Hunger" world.
5.) Don't have any.

I appericiate any help, thank you very much!

You have no triggers defined; https://www.spigotmc.org/wiki/learning-the-items-yml/#defining-an-items-triggers

Also, it's not "worlds" its "enabled-worlds".

You can check if you properly defined the item via /itemjoin list

Fixed items.yml; https://pastebin.com/vtduQsBf

Thank you very much!
It does work, but when entering another world, color codes aren't working properly.

This is how it's supposed to look (duh)

Sorry for the late reply, the only thing I could think of is another plugin stripping the color codes which is called item sterilizing.

A lot of random plugins do this like chat plugins, protection plugins etc, its just a matter of figuring out which one is causing it.

EDIT: Marking as resolved, please reopen this issue if it is still persisting.