I tried a few ideas but failed.

How would you detect if a creature has an crouch animation or not via a script?

Or can NO creature (even ones with weapons) ever perform any sneak/crouch animations (unless they are moded)?

see my next post.

ok, never mind, I went thru all the folders for all the creatures and there is no sneak animations.

But then, what do they do when the force sneak flag is set on them?

I cant remember what happens when you use force sneak.....I think from testing they will toggle on and immediately toggle off.

You can make creatures sneak by copying and renaming animations though.