Official portrait from close to her retirement, so she's about 120 here. Few visible new injuries, scowl +3, and reading glasses. And still perfectly capable of kicking ass.

There is no established military insignia that would be widespread enough to be recognized immediately by anyone so portrait artists use other kinds of symbols to make the status of their subject known. It irritates Eudoxia but the sign of her position as a captain, or commander of any kind is a pen, not a weapon. It tells that the person is at the top of the hierarchy, someone who signs orders and doesn't need to get their hands dirty. Her clothing then tells what that profession is that she is ruling over.