The Concubine Wants to Lie Down, but the Well Connects the Past and the Present

The heroine was originally a transparent girl who lived in the palace, but after traveling to modern times, an opportunity came and she transformed into a heartthrob! The second heroine is aloof and loves power but not the emperor~ Both of them are related to the secrets underground, and their identities remain a mystery. How do the heroines transform step by step? Please see below~