work papers vs working papers

work papers and working papers both are nouns.

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

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

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

Other synonyms of work papers include work permit.

work papers (noun)	working papers (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
	records kept of activities involved in carrying out a project