My guess is, not much. Had the Germans built her back in the mid 1930's and managed to work out all of the troublesome bugs inherant in everyday carrier-air operations, then, I'd say that she'd give a good account of herself against her enemies. As it was, the Germans were trying to take a giant step and rival the Royal Navy's Aircraft Carrier effectiveness, in one fell swoop, without doing all of the homework and painstaking study needed to bring it all off. In short, they'd be making it all up as they went along and that could quickly become costly in combat against the RN.