Ahhh! I see!
Now that you point it out, I see the differences very clearly. Thanks!
It is interesting what you say about the Paiwan, Rukai, and Puyuma sharing many cultural similarities. If I'm not mistaken, it is almost a parallel with the Atayal with whom the Taroko/Seediq and the Saisiyat share a lot of cultural similarities. And the laraw and it's sheath of the Tayal, Seediq, and Saisiyat share many similarities as well. They have the curved blade and either a wooden or metal socket handle. The sheaths all tend to be the "fish-shaped" kind. I don't know if the fish shape is intentional, since they range from fish-shaped to only abstractly fish-shaped depending on the piece.
Say, do you know if the Paiwan, Rukai, and Puyuma still have blades being made today?
I know for a fact that in Tahsi/Dasi there's some Hakka who make laraw for Tayal (mine was from there), and that in Tongmen, Hualien the Taroko/Seediq make blades as well... always good to see such traditions maintained.