troubler vs persona non grata

troubler and persona non grata both are nouns.

Word	Noun	Adjective	Verb	Adverb
troubler	Yes	No	No	No
persona non grata	Yes	No	No	No

As nouns, persona non grata is a hypernym of troubler; that is, persona non grata is a word with a broader meaning than troubler:

Other hypernyms of troubler include unwelcome person.

troubler (noun)	persona non grata (noun)
someone who deliberately stirs up trouble	a person who for some reason is not wanted or welcome
	a diplomat who is unacceptable to the government to which he is sent