Cosmetic surgery has been used as a plot device in all Star Trek series except Discovery and Prodigy as far as I am aware.
The Memory Alpha Cosmetic Surgery page details numerous instances of this happening.
This change is normally used as a plot device to allow crew members to interact with other races without those races knowing that the individual is from Starfleet.
As far as I am aware there are 2 instances were cosmetic surgery has been used in a "crime".
- Arne Darvin, a Klingon Intelligence operative appeared human to poison a shipment of grain.
- Thelev, appeared as an Andorian to sabotage the Babel Conference.
Cosmetic surgery appears to be easy, does not have any known side effects, can be reversed, can be done to the same person multiple times and also allows the changing of gender.
Are their any other known crimes undertaken by individuals who have had cosmetic surgery, or are there any in universe explanations on why this has not or could not happen?
I'm not including infiltration of an enemy base/ship as a crime as I would count it more as an act of war.