As far as an airbourne invasion is concerned...it may be usefull as part of a deception plan,with a phoney beachhead being established with a phoney maritime fleet made up of a mix of merchant and military assets,Taiwan would have to deploy some forces to oppose it...but really it would be just a nuicance,and add some confusion. And probably sacrificial!
I dont see the PRC sacrificing its elite airborne troops like that. Very bad for morale, first off, and in the modern age they could never keep it secret from the rest of their army like they could in Korea. Secondly there is just no point in sending your best troops to slaughter just for deception. It would make more sense to insert small cadres of saboteurs to raise hell behind the lines and tie up 10 x their number in enemy looking for them. But any airborne op wouldn't make any sense unless a airfield or port was the eventual target. Remember the end game objective of Overlord was a deep water port.
It would be interesting to discuss the resources needed for this op. This is what was available for Overlord, Land Forces—2l U.S. divisions (13 Infantry, 6 Armored, and 2 Airborne), 17 British divisions (l0 Infantry, 5 Armored, and 2 Airborne) and supporting troops of both Forces.
Air Forces—331 U.S. Squadrons (214 in Eighth [Strategic] Air Force, and 117 in Ninth [Tactical] Air Force) and 220 British Squadrons. Figures for each Air Force include squadrons of all types.*
Gasoline figures for allied vehicles alone were estimated at 5,000 tons per day and by D-day+5 the plan was for 29,562 vehicle to be off-loaded and 200,000 allied troops. Obviously these figures weren't met but it gives you some indication of the scope of such a amphib attack.
And 78 years later due to the precision and power of modern weapons such numbers no doubt wouldn't be necessary but the fact remains the Chinese would have to not only attack with a huge, rolling amphibious force, but would also have to supply it with a vast floating supply chain. Assets, btw, I doubt they have. Sure seizing a port would help but like the Germans in '44 I doubt the Taiwanese would leave a functioning port to the enemy.
More problems for the PLAN? Taiwan has a pretty good home made anti-ship missile called The Hsiung Feng IIE. It has good range, a 500 lb class warhead, is fairly stealthy, has a GPS capable guidance package, and can be launched from trucks. And they have at least 500 of them, this missile can also be aimed at land targets.
When I look at the big picture I must say however I dont see a whole lot of evidence for Chinese preparation for the Normandy type mass amphib OP. I would guess it would start with a massive bombardment of Taiwanese centers of power/military targets/communications by BMs, fighter bombers, and warships. At the same time I think they would launch one really big air assault aimed at getting an airfield, a port, and probably both. I think the Chinese watched Americas shock and awe campaigns very closely and they learned from them.
Such an OP would be far easier then the massive Normandy scenario. It would be far easier to hide somewhat as well, under cover of exercise. Even more important would be the goal to get a quick victory before America intervened. The Chinese appear to be arming for such a high tech limited operation, not the Overlord scenario.