I’m not sure if EvenSteven wants any more talk about Holdo’s hair (if so, let me know and I can take down this post), but since there’s been discussion here, I think changing her hair to brown is doable using colorista in After Effects, which has secondaries and power masks.
Here’s a sample:
https://vimeo.com/278972236
pw: fanedit
This would still require going shot by shot and animating the masks, but it does seem doable.