From Wikipedia:
An
Easter Egger is any
chicken that possesses the "blue egg"
gene, but doesn't fully meet any
breed description as defined in the
American Poultry Association's (APA)
standards, or in the case of Easter Egger bantams, the
American Bantam Association's (ABA) standards. The name derives from the resemblance of their colorful eggs to
Easter eggs. The
Araucana,
Ameraucana, and Easter Egger are descended from the same founder stock that spread around the world from
Chile and the
Falklands.
Commonly confused with the pure bred
Araucana and
Ameraucana, Easter Eggers are often sold under the name of one of the aforementioned. The majority of chickens in laying flocks that lay blue or green eggs are Easter Eggers.
[1] Commonly exhibiting muffs and beards, they generally resemble Ameraucanas. The color of Easter Eggers is particularly variable, and they appear in a great number of patterns.
So they technically are Easter Eggers. However, that term is unsatisfying since from both marketing and personal viewpoint perspectives. I would not recommend "muttbars" since there are many negative connotations with the term "mutt". At the show in Virginia last November, a breeder tried to argue that cream legbars were just mutt chickens, crossbreeds.
Most synonyms for hybrid are not becoming either. We would certainly want the term to be distinctive from Easter Eggers. I looked up synonyms for "colorful" since that is what these eggs are. The words that appealed to me was "prism" or "prismatic".
"Prism Eggers", anyone?