I recommend a novel where the female lead transmigrated. In it, a sister was reborn. Is the female lead low-key and smart?

In a novel, the female protagonist transmigrated and there was also a concubine daughter who was reborn as a legitimate daughter. The transmigrated female lead was low-key and smart. Although the mother of the female protagonist was a concubine, she was the daughter of the current Eldest Princess or something. Later, she was recognized. In her previous life, the reborn daughter of a concubine lived in the Inner Residence, so although she knew a lot of things, she did not have a good understanding of them. The ideas she came up with often did not have a follow-up. In the novel, there was once an empress and an emperor who had transmigrated. The two of them started to fight. Later, the man thought that the emperor and the woman were the empress. Later, the man betrayed the empress, and the empress killed him. The female protagonist was the daughter of the queen's daughter (the princess's daughter)(the daughter of the lost daughter).