I am not sure about faces. But I can vouch that they recognize hats.
I, as many of my farmer neighbors do, wear a straw hat in the summer. If I walk out to the garden in my straw hat, and there happens to be a deer there, it will give me that dull 1000 yard minimum wage stare and keep eating. Even if I yell and wave at it.
But one day I happened to have on my felt hat that I wear when hunting. There was a deer in the garden and she took one look at me and was out of there.
So for the garden, I immediately put an old felt hat on the scare-a-crow. And for next year, I will wear my straw hat when out with the bow 😀