Morax (Zhongli) is 6000 y/o and lived with Guizhong, lord of dust, and his followers.

When the war began 2600 years ago they both fought many gods and Guizhong ended dying, Zhongli took his people to the now Liyue harbor and there he soloed a lots of gods.

2600 years ago Barbatos (Venti) with the people of monstadt fought Decarabian, the god of anemo at the time. Barbatos later became the new God of anemo.

The war ended 2000 years ago, when it ended the 7 were crowned the Archons of their respective element.

In the 2000 Years that the war ended only two of the 7 originals remain.

The original 7 were crowned after a war so one must asume that the original 7 were the strongest and Venti himself said that Morax could sent him flying, maybe he is the strongest lore wise. (Not counting the gods from Celestia)