Android Pay launched in June of last year in Taiwan with only 2 banks under its wings: Chinatrust Bank and First Bank. Since then, it has expanded to more institutions including Cathay United, Union Bank, Shin Kong, Standard Chartered, Taishin International, E.SUN Commercial, Entie Commercial, Hua Nan, and it's now making its way to HSBC as well. According to the Android Pay page, all HSBC VISA and Mastercard credit cards can now be added to the Android Pay app in Taiwan, allowing you to use them for store and online purchases with merchants.
But there's also been a recent report from Focus Taiwan that debit card support is coming to Android Pay as well, and the first bank to have it according to the support page is Chinatrust. Others should follow soon though and all those debit cards in the "Unsupported" column should move to the "Supported" one. And yes, Google is still calling all of those Android Pay even though they're now under the Google Pay brand.