작가 (作家) -- perhaps because the 乍 part is sawing a branch off a tree is generally used in its sense of writers of words, but not always. Sometimes other "authors" such as composers (traditional music in these parts is written like words, BTW), illustrators, or choreographers, not just "artist" though but someone who creates something reproducible. It's specifically professional/specialist (家) "creative writers" of 작품 (作品), i.e. creative works, not biographical or other non-fiction work. More generally authors/writers are 저자 (著者).
저작가 (著作家) is a word, just not used as much. Maybe it sounds legal as 저작권 (著作權) means "copyright"? Heck, I tried . . .