I recommend "Song of the Phoenix in the Clouds" to you. This is an ancient romance novel. The female protagonist, Feng Jinghong, accidentally traveled to another world and swapped souls with the princess who was assisting the government. There were parallel spaces and multiple world lines in the story. The female protagonist became the overlord of the sea after the waves, and she dominated the business world and politics. This novel was suitable for the female protagonist to freely swap her gender, and it was an ancient style novel. I hope you like my recommendation. Muah ~