You can easily support both formats by keeping the overrides as always in the assets/minecarft/models/item/paper.json btu also use the new format for the assets/minecraft/items/paper.json
The client just ignores the stuff it doesnt need
Alternatively you can make an "overlay folder" where you override and add the new files

Tldr you can support both packs 👍 lmk if you want help with it

wiki

Oh, awesome, thank you! Learning new things all the time. I'll take a stab at it, and if I can't manage to figure it out I'll give you a shout.