fancy woman vs working girl

fancy woman and working girl both are nouns.

Word	Noun	Adjective	Verb	Adverb
fancy woman	Yes	No	No	No
working girl	Yes	No	No	No

As nouns, fancy woman and working girl are synonyms defined as:

fancy woman and working girl: a woman who engages in sexual intercourse for money

fancy woman (noun)	working girl (noun)
an adulterous woman; a woman who has an ongoing extramarital sexual relationship with a man	a young woman who is employed
a woman who engages in sexual intercourse for money	a woman who engages in sexual intercourse for money