quarreler vs controversialist

quarreler and controversialist both are nouns.

Word	Noun	Adjective	Verb	Adverb
quarreler	Yes	No	No	No
controversialist	Yes	No	No	No

As nouns, controversialist is a hypernym of quarreler; that is, controversialist is a word with a broader meaning than quarreler:

quarreler: a disputant who quarrels
controversialist: a person who disputes; who is good at or enjoys controversy

Other hypernyms of quarreler include disputant, eristic.

quarreler (noun)	controversialist (noun)
a disputant who quarrels	a person who disputes; who is good at or enjoys controversy