work papers vs work permit

work papers and work permit both are nouns.

Word	Noun	Adjective	Verb	Adverb
work papers	Yes	No	No	No
work permit	Yes	No	No	No

As nouns, work papers and work permit are synonyms defined as:

work papers and work permit: a legal document giving information required for employment of certain people in certain countries

Other synonyms of work papers include working papers.

work papers (noun)	work permit (noun)
a legal document giving information required for employment of certain people in certain countries	a legal document giving information required for employment of certain people in certain countries