I'm in Taipei often, and I've been here all November - honestly I have no idea where gay foreigners go. I'm totally non-scene, and the only foreigners I've noticed walking around are usually in Ximen - but the type you're looking for is very rare here, and likely fought over by locals like sharks tearing apart a sea otter.

Periodically I sit amused with my friend at one of the "bars" behind the red house where we sip fruit tea, and watch the goings-in from outside the bar, and sometimes you'll see your 'type' stroll by, eyes bulging out, covered with shopping bags, but my guess is they are tourists vs 'locals'.