The Agent Heiress: The Legend of Chu Li

She was a top modern-day secret agent. Betrayed by her comrades during a mission, she died alongside them. When she opened her eyes again, she discovered she had been reborn in a stranger's body in an unfamiliar world. Well, since she was here, she might as well make the best of it. But her new body's relatives had nothing to do with her! They'd better not provoke her, or she'd make them pay for it.