ill-scented vs foul-smelling

ill-scented and foul-smelling both are adjectives.

Word	Noun	Adjective	Verb	Adverb
ill-scented	No	Yes	No	No
foul-smelling	No	Yes	No	No

As adjectives, ill-scented and foul-smelling are synonyms defined as:

Other synonyms of ill-scented include fetid, foetid, foul, funky, noisome, smelly, stinking.

ill-scented (adjective)	foul-smelling (adjective)
offensively malodorous	offensively malodorous