transgressor vs wrongdoer

transgressor and wrongdoer both are nouns.

Word	Noun	Adjective	Verb	Adverb
transgressor	Yes	No	No	No
wrongdoer	Yes	No	No	No

As nouns, wrongdoer is a hypernym of transgressor; that is, wrongdoer is a word with a broader meaning than transgressor:

transgressor: someone who transgresses; someone who violates a law or command
wrongdoer: a person who transgresses moral or civil law

Other hypernyms of transgressor include offender.

transgressor (noun)	wrongdoer (noun)
someone who transgresses; someone who violates a law or command	a person who transgresses moral or civil law