OK, after that. Here the domestic political economy gets a bit tricky. OTL Taiwan got turned into the Japanese sugar island. But Germany grows beets. They also used Taiwanese hydroelectric power to produce aluminum, but demand was still limited before the development of duraluminum... and World War One is on the horizon.
Don't forget rice; bigger even than sugar by value, I believe.
Taiwan was just astounding, as colonies go. Japanese subsidies to the local government ceased in 1904; by 1922 it was sending tax revenue _back_ to Tokyo. (Mississippi, take note.) Massive trade surplusses. Real consumption per person on the island rose 20 percent in 1910-40; real GDP per person rose 55 percent. The place was financing _Japan_.
But lest one think the place was squeezed dry, note that over half of all Taiwanese made it out of primary school by 1940. Admitted, Japan itself hit this level in _1891_, but Mexico didn't manage to get half of primary-school-age children _enrolled_ until 1960, let alone graduated.