I’m not familiar enough with Breccia to comment on his expressionism, but I’m not sure I see the impressionistic aspect of Aristophane or Campbell. To a certain extent I can see it in Caniff at the height of his style (lots of black, minimal line work).

Sometimes I use the word “impressionism” to describe a painterly drawing: Milton Caniff, Aristophane, Eddie Campbell (who said a number of times that he likes impressionist painting). One could call the work of Alberto Breccia “expressionist,” I suppose. “Isms” from painting are a good tool if used wisely (for instance: it’s annoying when people just use “surrealism” as a short cut; how many times have we heard that Krazy Kat is surrealist?).