play-actor vs role player

play-actor and role player both are nouns.

Word	Noun	Adjective	Verb	Adverb
play-actor	Yes	No	No	No
role player	Yes	No	No	No

As nouns, role player is a hypernym of play-actor; that is, role player is a word with a broader meaning than play-actor:

Other hypernyms of play-actor include actor, histrion, player, thespian.

play-actor (noun)	role player (noun)
an actor who travels around the country presenting plays	a theatrical performer
	a person who makes deceitful pretenses