I have seen a few over the years, but you come across them by chance usually.
They set up for say a month and sell past stock sports gear at cheaper prices. There is Adidas, Puma etc, to the crap like Adicas and ike
Does anyone know any current stores in Taipei or New Taipei City?
Not sure about Temp stores but there are a few around NTU campus that seems like an Outlet of these sport brands.
Try Xinsheng South Rd, Gongguan MRT station. Might worth a look?
Anything for the South? They rented an town government building in Pingtung believe it or not Pretty good prices. Sure came in handy for a large family. My wife learned about it from a chat group the last minute.