Recommend me drama where FL is send to ML company or for marriage alliance(Historical/wuxia) by villain to spy on ML but they fall in love and she regrets it and helps ML "defeat" Villain.

no love triangle please, it can be love triangle without annoying or evil SFL/SML.

Thank You.

https://mydramalist.com/62635-oh-my-sweet-liar

Oh My Sweet Liar

In this FL was sent to ML house for extracting something ..... ML caught her and asks her that if she wants to avoid punishment then she has to act as she is pregnant and want to get married ... as he wants to avoid another  arranged marriage

My Name - she isn't per say send to a company but to the police force.
The Secret Life of My Secretary - she works for him but doesn't like him. Something happens and he mistakes her for the daughter of a CEO from a different firm.
Stealth Walker - she is an undercover cop and tries to figure the "villain" out. But what she learns instead is a lot different than what she expected to find

Maybe: 

  • Empress Ki
  • Spy Myungwol
  • Miss Ripley
  • Hateful But Once again
  • Spy