perfunctorily vs pro forma

perfunctorily is not an adjective while pro forma is an adjective.

Word	Noun	Adjective	Verb	Adverb
perfunctorily	No	No	No	Yes
pro forma	No	Yes	No	Yes

As adverbs, perfunctorily and pro forma are synonyms defined as:

perfunctorily and pro forma: in a set manner without serious attention; as a formality

perfunctorily (adjective)	pro forma (adjective)
	done or produced as a formality only

perfunctorily (adverb)	pro forma (adverb)
in a set manner without serious attention; as a formality	in a set manner without serious attention; as a formality