Charlotte d'Éon de Beaumont or Charles d'Éon de Beaumont (5 October 1728 – 21 May 1810), usually known as the Chevalière d'Éon or the Chevalier d'Éon, was a French diplomat, spy, and soldier. D'Éon fought in the Seven Years' War, and spied for France while in Russia and England.
D'Éon had androgynous physical characteristics and natural abilities as a mimic and a spy. D'Éon appeared publicly as a man and pursued masculine occupations for 49 years, although during that time, d'Éon successfully infiltrated the court of Empress Elizabeth of Russia by presenting as a woman.
Starting in 1777, d'Éon lived as a woman and was officially recognized as a woman by King Louis XVI.
You can read about d'Éon's amazing life at Wikipedia here: https://en.wikipedia.org/wiki/Chevali%C3%A8re_d%27%C3%89on
Image: By Thomas Stewart, https://commons.wikimedia.org/w/index.php?curid=19455161