There are quite a few novels that fit this plot. I recommend the following ones to you: Fake Eunuch: From Meeting the Empress to Dominating the World, Fake Eunuch: Breaking the Emperor's Daughter Body at the Beginning, Fake Eunuch: Breaking the Emperor's Daughter Body, Forgive me, Your Majesty, I don't know! After Being Forced to Marry for 9,000 Years. I hope you like my recommendation.😗