If I were Taiwan, I would be purchasing some nice, modern, quiet diesel submarines. They can afford it.
Funny, though. There are a lot of ChiCom mouthpieces like the Asia Times and Business Insider who pooh-pooh it, say it would never work, it is a waste of time, blah blah blah.
Bottom line, the ChiComs are going to have to cross a body of water to take them over, no matter what. They won’t be able to airdrop their all troops in or supply them via an airlift.
After a few transports go down...
Taiwan needs to beef up their antiacraft capabilities as well.