I've made the plugin that you've requested.
Now since you want the set area like WorldEdit, I had to add a command that actually sets...
If you're willing to use & force other players to use a resource pack then it can be done without replacing the actual iron armor
Happy to help!
Hey, here is your request: https://github.com/PixelisMania/Multiverse-Gui
This is my first public plugin so if there's any problems then tell me.
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