You mean as in so they never play, or so that something triggers them to start/stop?
If the former, it should be as simple as finding where the animation file is referenced to play in whatever section of the xml, and remove that part or add a trait that tells it not to play or to do nothing.
That said, depending on how the models/animations are set up, and how the engine displays them by default, it may come out looking odd. I would guess it would just revert to a T pose, though, for humanoids.