How to connect Blockbench Animation variable to an Mcreator Variable / Block NBT?

I was wondering, since there is variables in the Blockbench animation editor, is there a way or format to CONNECT the animation variables to MCreator variables such as NBT?
The reason is so I can easily make a custom liquid-container visual based on how much of a certain item it contains.

I don't mind if it requires custom code or editing the animations in question.
NOTE: The block is animated using Geckolib, incase that changes anything (it shouldn't, the variable system is pre-built into Blockbench w/out any plugins).