Actually it is.
I was discussing something akin to the "flight deck cruiser" schemes developed (but never built) by several navies in the 1930's. A 10,000 - 15,000 ton heavy cruiser armed and armored for surface combat but with a full-featured hangar and flight deck (aft, forward or midships, depending on the design) capable of handling between 10 and 20 traditional carrier-borne aircraft. Probably the closest anyone came on practice was the Japanese Tone-class cruisers, but these only shipped floatplanes on their large aft aircraft handling deck.
When compared to US and Japanese fleet carriers, Graf Zeppeln would have simply been an obsolescent, over-armored and under-capable aircraft carrier.