The diferences were in the beefed up landing gear and the tail hook, along with the forward stabilators which they have already mastered with their six prototypes.
IOW, they already know pretty much how to fly them...but not from carriers and that is where there learning curve is about to begin. And, like America, they are going to lose some aorcraft and pilots in the learing.
I would not be too sure to dismiss this threat. The Chinese appear to have stealth bomber and fighter variants that will probably be ready to go sooner than later.