This is one of the most frustrating questions. to clarify breed, the Americana species, sometimes called Americauna, is white with black tipped tail feathers and black speckles and spots around the wattles and neck. the shank is a slate blue color. the Aracauna chicken is mainly tan- brown with black speckles on all parts of the body. the shank is more of a green- blue color. the Americana lays blue, pink, and [rarely] purple- ish eggs. the Aracauna lays a greener color. As for temperment, they are both sweet with an attitude. as with all birds, it depends on how they were raised as chicks.
-- i hope this can help.