Minecraft, modloader and mod versions
Minecraft: 1.20.1
Fabric: 0.16.14
Soulslike-Weaponry: 1.3

I'm not sure if I'm doing something wrong, or if the recipe just displays incorrectly here, but I can't seem to be able to craft this potion. I tested this using only soulsweapons and its listed requirements for fabric to make sure it wasn't an issue with a different mod.

Good catch, will fix that.

Minecraft didn't like having modified potions turned items included to the recipe, fixed it by changing how they are crafted.