Custom Model Data Menu

[hexed cypress]

is it using datapacks or is it using mods for these custom items?

hmm, how complex would you say the items are? do they have functionality or are they just for holding/crafting, and if functionality is it based on another item's functionality or implemented through a datapack?

Depending on the effort you want to put in, my suggested solution is Polymer (https://github.com/Patbox/polymer), which is a very powerful project for making these items fit better with vanilla while keeping client requirements to just vanilla + a resource pack