Continuing to develop my au, I really want a Zhongli who, by his very presence, inspires awe of the gods and spirits.
A lone figure on a mountainside, a man meditating in the rays of dawn. A light breeze ruffles his long brown hair and kisses his cheeks. His head is crowned with amber horns, his arms are dark with golden patterns running down them, and a long tail covered with shiny brown scales is wrapped around his legs.
It's easy to understand that this is not mortal, perhaps some kind of inventive ghost, but as soon as that sharp amber gaze falls on you, you understand with all your gut that this ancient being can be nothing but the God.
Initially, I imagined that Venti and Zhongli would appear in the TGCF world sometime during Xie Lian's 800-year exile. But once in a completely different world, our Archons lose something important - knowledge and participation in historical events. Yes, they have 2600+/6000+ years of experience, but this is the experience of their world.
So instead, I decided to place them about 100 years before Xie Lian's first ascension)
Our Archons travel to a new world, learn about their Gods, ghosts, culture and history. Did Zhongli visit Xianle? Perhaps he even saw/met the young Xie Lian? Venti might have crossed paths with the little fire spirit Wu Ming.
Venti: What a cute little flame. Come here, I'll help you rest.
Fire spirit Wu Ming: *flies away and flickers violently*
Venti, tilting his head to the side: Oh, you don't want to leave? Anything left to do?
Fire spirit Wu Ming: *nods*
Venti: Is it a person? If so, I can help you find them!
(P.S. If Venti really helped find Xie Lian that time, then the way Hua Cheng later accepted Venti's "the year of alcohol/the search for a loved one (Xie Lian)" bet puts it in a new light :D)
It would be especially tragic if Venti found Xie Lian after the "Hundred Sword Strikes". He would definitely have helped Xie Lian get out, but he would have been forced to leave, leaving the blessing "take care of your beloved, Little Flame". (Or not, depending on how much you're willing to change the plot of the canon.)
But let's digress a bit from the canon.
I want to give Venti and Zhongli a cult following. So that people could pray to them and build temples, but the Heavenly Officials couldn't figure out who the hell these God of Contract and God of Freedom are.
It probably all started with the fact that Zhongli and Venti helped some village with a ghost or a curse, and the residents were like,
People: Thank you so much, tell us which god do you worship so that we can pay homage to him?
Zhongli: Oh, no, it's absolutely no-
Venti: You can pray to Morax!
People: Morax? Who is it? We have never heard of such a god.
Venti: He's not very well known in these lands. But he's a master of martial arts, and contracts!
People: Contracts?
Venti: Yeah! If you want to make a deal or contract with someone, then pray to Morax, and then if one of the parties violates the contract, he will personally punish them! Ehe :D
Zhongli: But if your problems are more mundane, you can pray to Barbatos. He is good at giving advice in relationships, as well as guiding the lost ones.
Venti: Hey! (Are you giving me extra work, old man?!)
Zhongli: En. (Just like you, drunkard.)
And so, slowly, they gather believers. After actively wandering for 200-400 years, Zhongli settled in the mountains near the village (which later grew over the centuries and began to flourish. Perhaps even a country was formed there, and at the foot of the mountain there is a statue of the Dragon and the Bard that people worship), and Venti continued to wander.