musicianship vs prowess

musicianship and prowess both are nouns.

Word	Noun	Adjective	Verb	Adverb
musicianship	Yes	No	No	No
prowess	Yes	No	No	No

As nouns, prowess is a hypernym of musicianship; that is, prowess is a word with a broader meaning than musicianship:

musicianship: artistry in performing music
prowess: a superior skill that you can learn by study and practice and observation

Other hypernyms of musicianship include art, artistry.

musicianship (noun)	prowess (noun)
artistry in performing music	a superior skill that you can learn by study and practice and observation