Huh, what a unique and beautiful color. My first instinct would be to call her a grullo but without a dun parent or a dorsal stripe, I don't think that is possible. My next thought was a dark bay but that doesn't fit either because she doesn't appear to have black stockings either. My best guess would be a brown but I couldn't be sure LOL. As for the roaning, I am willing to bet that is a product of her paint pattern, especially since neither of her parents are roan, not to mention that it is also present on her face.
There is a place you can send some of her DNA and have them run a color test but I can't remember where it was. There is a member here called CheyAut that would be able to tell you who runs the tests. That may be your only way to get a definitive answer LOL.
Beautiful horse either way.
Oh, and welcome to the forum
Edited to add: Oh!! I wonder if she could be a form of Liver Chestnut. That would certainly make sense