byproduct vs consequence

byproduct and consequence both are nouns.

Word	Noun	Adjective	Verb	Adverb
byproduct	Yes	No	No	No
consequence	Yes	No	No	No

As nouns, consequence is a hypernym of byproduct; that is, consequence is a word with a broader meaning than byproduct:

byproduct: a secondary and sometimes unexpected consequence
consequence: a phenomenon that follows and is caused by some previous phenomenon

Other hypernyms of byproduct include effect, event, issue, outcome, result, upshot.

byproduct (noun)	consequence (noun)
a product made during the manufacture of something else	having important effects or influence
a secondary and sometimes unexpected consequence	the outcome of an event especially as relative to an individual
	a phenomenon that follows and is caused by some previous phenomenon