burdensomeness vs difficultness

burdensomeness and difficultness both are nouns.

Word	Noun	Adjective	Verb	Adverb
burdensomeness	Yes	No	No	No
difficultness	Yes	No	No	No

As nouns, difficultness is a hypernym of burdensomeness; that is, difficultness is a word with a broader meaning than burdensomeness:

burdensomeness: unwelcome burdensome difficulty
difficultness: the quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result

Other hypernyms of burdensomeness include difficulty.

burdensomeness (noun)	difficultness (noun)
unwelcome burdensome difficulty	the quality of being almost beyond one's ability to deal with and requiring a great effort to achieve a positive result