This is a resource pack that essentially adds all of the Twilight Forest, Mutant Creatures and Aether content in the Legacy4J crafting system :)
If you are wanting to use the Legacy4J crafting GUI with Twilight Forest, Mutant Creatures and The Aether this is the resource pack for you.
Please bare in mind that you do not need to have all mods for this resource pack to work you can have any of the three in whatever order and it will still work with all of them!
I imagine in the future there will be easier fixes for the Legacy4J mod support but for now this is the easiest way.
If you have any questions or issues go to the Legacy4J discord and head on over to posts under the community section and find the post called "Twilight Forest and The Aether and Mutant Creatures in Crafting GUI"
Enjoy!