I wouldn't consider her stance predatory or aggressive. My beardie stares at me sometimes — I think he just likes to watch me. Maybe wondering why I pester him all the time. :lol:
Here's an example, he's making a very similar face to the one your beardie has in your first couple of pictures.
He sat like this in the
bath for a few minutes and then climbed out onto my hand — no defensive behavior despite his stare-down. In fact, right after I dried him off, he snuggled into me to try and sneak a nap.
If your beardie were feeling defensive/unhappy/etc., you'd likely see her puff up or open her mouth at you or, as kingofnobbys mentioned, you'd see her beard go dark under her throat.