Not really no. It's already quite difficult to get a build environment up and running, just the build the game as is.
If you'd really want to, installing WSL would be the first step, there's a tutorial for that
here. So you can see if that's something up your alley.
After that you would need to update it, install the packages required for KeeperFX. Get the source code from github, make the modification you'd want, and in your Linux app build your source.
What I did in the screenshot above was simply raise the size off the creature images, and you see it leads to complications already. You'll notice a sleeping reaper has a small chair attached, which is displayed on top of the originally sized chair that is his lair. I'm confident there would be many more issues like that you'd need to figure out and solve.
Having it be for just a specific creature model is not much of a complication, the code I linked shows how to set a different size when affected by a specific spell, the same way can be done for a specific model.
Long story short, this most likely won't be worth your trouble.