Old school or new school. Still need boots on the ground to occupy. A blockade could work in theory. It's success would depend on United States resolve to intervene. I feel the best way for China to crack the nut is through subversion and a fifth column. I know there are already those in Taiwan who work for China. If I was China I would continue to expand infiltrators until you own the island outright. It's not like there's a rush on taking over Taiwan