How do i get weapon aspects

[MeltedLemonade]

I know they exist, where can i activate them or see how to craft them cause all i can see is the crafting the weapon screen and selecting the weapon on the dial

[MixelPixel]

You need to have beaten Hecate a couple of times and eventually you'll get new dialogue regarding aspects which unlocks the incantation you need to brew to unlock them

EDIT: Don't know how many times you need to beat her though, just keep beating her

[Nikolaus]

For me it happened after I unlocked all weapons and then beat Hecate again and she gave me the Incantation for it.

It's quite cheap to unlock if I remember correctly but it requires bronze that you get from the Surface.