"Regardless of whether or not a player has completed the side quest "A Vital Title," they will be able to purchase a Zodiac Weapon replica from the NPC Drake in the North Shroud (X:30.3 Y:20.1) if they meet any of the following conditions:
They currently possess any Zodiac Weapon Zeta.
They have exchanged their Zodiac Weapon Zeta for an Astral Nodule and Umbral Nodule."
so this doesn't mean that we can get any zeta replica? it's kinda misleading.