Interchanged

What would you do if you were given a chance to live someone else's life? She was a genius alchemist and a deadly assassin in her past life. She chooses to live in the 18th century as an unwanted princess in order to settle the payment and avenge the soul of the previous body. However,she had changed a lot of things that shouldn't be changed. From wearing breeches to forging guns and from concocting poisons and explosives to raiding tombs... from wooing ladies in her male disguise to forming a bandit freedom fighters. All in all, she's a crazy badass heroine.