As far as I've noticed the Bow and Crossbow are the only weapons this happens with. With either of them equipped, if you draw an arrow/aim while already moving, you continue to move but slow down as usual and are able to move in any direction. If you draw/aim while standing still, and then try to move, you don't. You're stuck in place. This also happens while crouched.
Character stuck in place when Bow is drawn while standing still. (2 comments)