You definently need a Dual stamp. I'm not sure if there are B or A grade Dual stamps. I believe there are just Dual stamps.
To make A duals, get two B grade swords, some AA, 1 dual stamp, don't remember on Jems, IF any, although I think you do need Jems there as well of A grade.
You need from 1.7-2mill ish AA. A dual stamp (they are universal work to make all duals) and these swords:
Keshenberk or Damascus. You can put those two swords into any combination you like to form 3 different duals. Kesh*Kesh=8% atk speed Kesh*Dama=25% HP Dama*Dama=ACC+6
Keep in mind that I think it's not just any b grade swords at this point, the only b grade swords you can make a grade duals from right now as far as I know are a Keshanberk and a Sword of Damascus and any combination of those two [kesh*kesh, kesh*dama, and dama*dama].
imo... ncsoft kinda did something stupid..... why so little choices.. specially considering that S grade you only get 1 choice of duals? usually the higher up you go.. the more diverse things shouldget.
Its no different to other weapons. At A grade you got what, 3 different duals to choose, where as for a single handed sword i can only think of 2 which are designed for melees, DLE and tallum blade.
More S grade will be released for sure, no sense giving it to us all at once.
Im a PvP gladiator, there is no excuse in my view to lose 8% attack speed, which is vital for skill re-use timers and charging focus sonic, over what is a really small amount of P atk, i mean c'mon, its not even noticable.