All I can say is... they look like good blades.
They look Paiwanese, but Rukai and Puyuma (being related) have similar designs and I'm trying to get better at distinguishing. I've also noticed by the way that oftentimes Western collectors are very keen on distinguishing between different types, where-as a local might just call it x y or z, end of story.
I find it interesting that the paiwan were actually a more hierarchical (matrilineal) society and had a more organized military than many other tribes. They used long spears, shields, takit, and bows and guns. I've often wondered what has been lost... Taiwanese aborigines, on the plains, were known for their archery skill, as well as sparring with sticks to the beat of drums, and for their spearplay and wrestling. As with many aboriginal cultures, a lot of martial practice has been lost, even moreso than a lot of "civilizations" which have also lost a lot of their martial traditions.
I wonder, however, how the southern cultures came to adopt the almost zhibeidao or wakizashi looking blades, is it a relic of ancient Chinese influences from say the Han or Tang Dynasty???
In the north areas, "Atayal" and related groups tended to use curved blades, called laraw in some dialects. There are straighter versions of laraw which resemble some Taiwanese (Han) and southern Chinese knives and shortswords, like the butterfly sword.. particularly blades often attributed to the Sakizaya. The laraw topuw, the "radish" shaped cleaver-like blade also looks a lot like blades sometimes used a polearms in the old days by Taiwanese militia.
Having said that, most Southern Chinese blades that did have sockets had wooden handles, where-as many Taiwanese aborigine blades had socket-handles like the Philippine tribes of the Luzon... Taiwanese smithying is a bit of a mystery, often Han settlers made the blades for them, yet there was definitely ethnic preferences and a design in mind.... and there is some evidence of metal working before Han settlement... the creation and abandonment of pottery in areas... the past of a maritime culture but replaced by a general fear of the sea... mysteries we may never unravel.
Taiwan has a rich martial history, which is maybe under appreciated. Maybe varta or yuanzhumin will comment, they know quite a bit about this stuff.