Do you guys see that thing in her hair? Isn't that a kanzashi of some sort? Could she be of japanese origin, but dressed up like 15th/16th century nobility? I've never heard of such a thing, but Idk. It might be possible. Just saying
I've never seen this portrait in my life before and I've seen tons (had a history crazy, or well, had. It's lasted from I was around 6 until now, hehe).