1. Answer: It depends on everyone's taste and these rankings change all the time. According to RankMyPorn, at the moment, the top ranked Mixed Ethnicity Female Pornstars in the world are: Zaya Cassidy, Mia Lelani, Gianna Dior, Eva Lovia, Uma Jolie, Satin Bloom, Roxy Lips, Darcia Lee, Amirah Adara, Vienna Black, but these will change based on what people vote.
2. Answer: It changes. You can see the latest rankings on RankMyPorn.com and also vote on it for free.