I believe in the Void Century/before it there were not 3, but 11 (9+2) “Weapons”.
These “Weapons” were not actual weapons, but instead incarnations of ancient powers/wills that defied the rules of the world.
Betrayed
Nika(Sun): Power of Creativity/Creation
- Not the Devil fruit, but instead the “thing” known as Joy Boy. I believe that they are completely separate entities. While the Gomu/Nika fruit allows Luffy to access the Gear 5 state, I don’t believe that it is the only way to access it OR possibly that Joy Boy is the “Key” to unlocking it.
- This power would give its user the ability to do pretty much whatever is in their imagination.
- It could potentially be a “catch all” for every other power on this list depending on how its user uses it.
Pluto: Power of Ships(Klabautermann control)
- I think that Pluto(Pluton) is/was a being that was capable of speaking to any and all ships. This person was able to create the biggest warship known to mankind with a personality that did not allow any enemy to control it. Pluton(the ship) is different from Pluto(the person). Pluto the person/power is still something that exists in the world today. Some “candidates” for who might have this power are Franky or Usopp (both have ways of communicating with ships).
Poseidon(Neptune): Power over Sea(Sea King Control)
- Obviously we have seen who Poseidon is so I don’t have to get in depth into what this power is. I believe all of the other “Powers”/”Ancient Weapons” are identical in the fact that they are passed down through history.
Uranus: Power over Sky (Weather Control)
- This power would allow someone complete control over the weather. Not just “make it rain” or “thunderstorm”. This would allow the user to turn an island from a winter island into a summer one. They would be able to command the skies to fire lightning down onto their enemies similar to Enel.
Betrayers
Saturn: Power over Time
- This person would have a power that allows them to momentarily freeze or slow down time for people/objects. This would allow certain important things from the Void Century to be passed down. It might also allow the user to extend the lifespan of themselves/others.
- The current “User” of this power is the Gorosei Member “J Garcia Saturn”.
- The reason I think this power exists is based on the god Cronos also known as Saturn who governed all of time.
Mars: Power over Anger (Emotion Control)
- This person would have the power over others in an identical way to Ms Wednesday but on a completely different level. They would not have to show the user a specific picture, instead they would be able to just “force” the emotions onto someone.
- I believe this power is currently possesed by the “Wano” esque Gorosei member.
- Mars was the God of war. War causes anger.
- This power could previously used to cause many wars throughout history by angering the people without their knowledge.
Jupiter: Power over Faith (Belief Control. A “Forget me” power and what created the Void Century)
- This person would be able to make entire kingdoms of people/possibly the entire world forget anything they desired.
- I believe this power was used in Lulusia which caused the entire world to completely forget its existence. I also believe this power is used fairly “commonly” and there are many islands that we dont know ever existed.
- This power would be similar to the “Hobby Hobby Fruit”. No person would be immune to it.
- Jupiter was the God of all other Gods. They were in command of all others.
Venus: Power over Demons (Devil Fruit Control. Can stop/control devil fruits)
- The god Shukra, also known as Venus, consoled all of the demons.
- This power would allow the user to completely stop all devil fruit powers within its vicinity.
- I believe the user will use this power on Luffy, but not be able to pull him out of Gear 5th(as its not strictly a devil fruit power imo).
Mercury: Power over Distance (Teleportation, Hermes)
- Hermes, also known as Mercury, was the messenger for the gods.
- He was able to travel between realms at will.
- I believe this power would be similar to many others, The door fruit, Kuma’s paw, etc.
Finally we have:
Luna: Power over the Moon
- I think this power would be something like an opposite to the Sun God Power.
- It would allow its user to restrict “Creativity”/”Imagination” in someone.
- I believe that the Minks are the origin of this power and draw their abilities + Sulong from it.
- The current possessor of its “copy(the fruit, like Nika fruit)” would be Blackbeard.
- It wouldn’t be/want to be be part of the original 9, but he may want to destroy the current 5.
Gaia: Power over Earth (the map thing in Chapter 1060)
- This power would give its user the ability to alter the earth.
- They would be able to draw on a map and create islands as well as destroy them.
- Imu would be the current user of this power
- I believe that this power wasn’t originally included in the 9 which is why Imu betrayed everyone.
*Theory by Harmonious