So basically more space in hangar for maintenance without port elevator? Does it affect sortie rate/time?
It depends on the elevator size, speed, and the hangar layout. The Nimitzs have 4 elevators but clearly that was a little excessive so they adjusted that to 3 for the Fords.
Part of it has to do with US carriers having smaller airwings compared to before. Whereas you can theoretically stuff each CVN with 80+ aircraft, moving them around the ship becomes a nightmare, and they realized they were better off downsizing to ~50 where each aircraft has adequate space for maintenance, handling, etc. With fewer aircraft on board, you don't need 4 elevators to toss to and from the flight deck at breakneck pace.
The 003 having 2 elevators is a little bit strange, considering that if one of them were disabled or malfunctioned, it would cut its sortie rate in half. But assuming they both worked properly, and that each elevator is large enough to fit two fighters, it should be sufficient. And also unlike USN carriers, there are only 3 catapults to launch from, not 4, so that is an existing constraint to sortie rate that perhaps 2 elevators can quite readily meet. After all, it doesn't make sense to have only 3 catapults, but also 3 or 4 elevators that can shuttle planes onto the flight deck faster than they can be launched.
If they are confident enough in their elevators, they can always run them a little faster to compensate for having only 2 of them. Overall, 2 elevators running speedily delivering aircraft to 3 catapults, should be about as effective as the Ford's 3 perhaps less speedy elevators delivering aircraft to 4 catapults, in terms of sortie rate.