mischievousness vs impishness

mischievousness and impishness both are nouns.

Word	Noun	Adjective	Verb	Adverb
mischievousness	Yes	No	No	No
impishness	Yes	No	No	No

As nouns, mischievousness and impishness are synonyms defined as:

Other synonyms of mischievousness include puckishness, whimsicality.

mischievousness (noun)	impishness (noun)
reckless or malicious behavior that causes discomfort or annoyance in others	the trait of behaving like an imp
an attribute of mischievous children
the trait of behaving like an imp