Considering sequential art is a chain of images, such as comics or storyboards, you can infer that a sequential artist is one that draws comics, storyboards, etc.

Sequential art can be worth from $10 for a comics sequential art book to millions of dollars for antique sequential art sculptures and engravings. Sequential art is portrayed by the use of several images in order to develop a story or to prove a point.

William Eisner has written:

'Comics and Sequential Art'

Some alternatives to comics are graphic novels, manga, webcomics, illustrated books, and animated series or movies. Each of these forms offers a unique way to enjoy storytelling through visuals and text.