Why an operational Graf Zeppelin would attract intensive attack

How effective could a completed Graf Zeppelin be, especially with navalised Fw 190s after 1942?

The aircraft could be effective, but the carrier's reach would make it an urgent target and its survival doubtful.

Graf Zeppelin was a carrier, despite the question's description of it as a hybrid. An operational ship would have been a high priority for the Royal Navy and RAF. Its aircraft could search farther and attack distant targets beyond a surface raider's immediate reach. To survive until 1942, it would probably have had to remain hidden. A hypothetical navalised Fw 190 could have been a strong aircraft if the carrier survived to receive it. The expected British effort against this single carrier would exceed even the campaign against Tirpitz.