frankness vs forthrightness

frankness and forthrightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
frankness	Yes	No	No	No
forthrightness	Yes	No	No	No

As nouns, frankness and forthrightness are synonyms defined as:

frankness and forthrightness: the quality of being honest and straightforward in attitude and speech

Other synonyms of frankness include candidness, candor, candour, directness.

frankness (noun)	forthrightness (noun)
the quality of being honest and straightforward in attitude and speech	the quality of being honest and straightforward in attitude and speech
the trait of being blunt and outspoken