In case you ever need ideas for unique weapons, do what I do-
Go to this website, and pick a weapon from their huge list. Try to find something you haven't heard of or seen used very much.
https://www.d20pfsrd.com/equipment/weapons
Once that's done, if you want to make it magical and have unique abilities, just use the magic weapon creation chart from the same website.
https://www.d20pfsrd.com/magic-items/magic-weapons
No one needs to know that you're using game templates to write your fantasy world, but trust me when I say using things like this is a massive boon for developing unique content quickly.