Hello Spongie, Im the creator of the Dynamic Body Shape Mod, which dynamically changes your character and zombie characters appearance and weight according to their weight.

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3066054201&searchtext=

Part of the mod Adds to the character textures (to make them look like they have muscles, or that they are underweight, etc), which I learned this mod does something similar too.

Would you be interested in working together on that aspect?