How to create new NBT tags for vanilla Block Displays and Item Displays in 1.20.1?

[ItsErtHere]

I want my mod to add two new NBT values to Block Displays and Item Displays (Like left-rotation, scale, transformation, etc.), which I call texture_repetition and texture_shift (both Vector3f variables). Texture_repetition allows the Display to repeat its texture or only show part of it, and the texture_shift value allows you to shift to the part of the texture you want the display to show. I already tried Mixins, and I assume I need to use the renderstate() function and entityData variable, but entityData is protected, which means I can not edit it using Mixins. How would I add these NBT values to the Display class without using the entityData class?

(These two data values, if coded correctly, could allow slabs/stairs/walls of any block to be represented using Displays without being limited by the vanilla inventory options)

Edited June 25 by ItsErtHere
Explaining applications for my additions

[ItsErtHere]

I will repurpose this question for 1.21, for any future answers