sincerity vs naturalness

sincerity and naturalness both are nouns.

Word	Noun	Adjective	Verb	Adverb
sincerity	Yes	No	No	No
naturalness	Yes	No	No	No

As nouns, naturalness is a hypernym of sincerity; that is, naturalness is a word with a broader meaning than sincerity:

sincerity (noun)	naturalness (noun)
the quality of being open and truthful; not deceitful or hypocritical	the quality of being natural or based on natural principles
the trait of being serious	the likeness of a representation to the thing represented
a quality of naturalness and simplicity	the quality of innocent naivete
an earnest and sincere feeling