Rikan Koukoku Hikikomori Zuichou Hiden - Hibi Koukyuu no Nukedashi, Yuunou Kanri Yattemasu.

A reclusive princess who rarely shows her face, and a competent official who rose to the second highest position in the Ministry of Civil Affairs in just five years. The story of a princess who dons male garb and uses her two identities to solve the country's crises one after another! A Japanese girl, Saya, wanders into a Chinese-style world where black is considered a noble color reserved for emperors and queens, and is picked up by the emperor of the Rikan Empire to become his consort. However, she finds her life too boring, so she escapes from the palace, dresses as a man, and starts working as a government official... and before she knows it, she's promoted to the top! She hides the fact that she has black hair and uses her two faces, "reclusive queen" and "competent official," to solve problems that threaten the court and the country!