bemusement vs mental confusion

bemusement and mental confusion both are nouns.

Word	Noun	Adjective	Verb	Adverb
bemusement	Yes	No	No	No
mental confusion	Yes	No	No	No

As nouns, mental confusion is a hypernym of bemusement; that is, mental confusion is a word with a broader meaning than bemusement:

bemusement: confusion resulting from failure to understand
mental confusion: a mental state characterized by a lack of clear and orderly thought and behavior

Other hypernyms of bemusement include confusedness, confusion, disarray, muddiness.

bemusement (noun)	mental confusion (noun)
confusion resulting from failure to understand	a mental state characterized by a lack of clear and orderly thought and behavior