I was a little surprised but my pilot for the HKG
leg didn't even try to change route. I suppose part of it is because at that range, your wiggle room is very low -- you can't really find alternative routes since typhoons are huge (you'll have to take a long detour). At the end it wasn't that bad.
My uncle has flown from TPE
once when the whole flight was basically in a typhoon (which was heading towards Hong Kong), and we were all in Hong Kong hoping that the flight will be ok. He said he felt like he was flying in a kite for most of the flight. The worst thing was -- by the time they got to around HKG
(they were already over the city, basically) the pilot decided that the conditions were too severe and didn't want a risk a landing -- so they flew all the way back to TPE
! What a waste of two nervous hours.