byproduct vs upshot

byproduct and upshot both are nouns.

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

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

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

byproduct (noun)	upshot (noun)
a product made during the manufacture of something else	a phenomenon that follows and is caused by some previous phenomenon
a secondary and sometimes unexpected consequence