bare-knuckle vs bare-knuckled

bare-knuckle and bare-knuckled both are adjectives.

Word	Noun	Adjective	Verb	Adverb
bare-knuckle	No	Yes	No	No
bare-knuckled	No	Yes	No	No

As adjectives, bare-knuckle and bare-knuckled are synonyms defined as:

bare-knuckle and bare-knuckled: characterized by disorderly action and disregard for rules

Other synonyms of bare-knuckle include rough-and-tumble.

bare-knuckle (adjective)	bare-knuckled (adjective)
characterized by disorderly action and disregard for rules	characterized by disorderly action and disregard for rules