The not-quite-sigh seems to come as much from the vehicle as the projection. And while Optimus doesn't know what a 'Lawmaster' is, he at least knows enough of the culture to, along with context, get the gist of her words. "It is," he agrees, before moving on. "Does that mean you have an idea of what has brought me...us here?" he corrects, 'looking' at her with false eyes and full vision sensors both.