this is a really good idea (though I didn't completely follow your prompt) but it sparked a lot of thought! sorry for the angst though!

Shortly after Zhongli’s retirement begins in earnest, the Eleventh Harbinger disappears. Not even Ningguang’s extensive network of spies can say where he is. It’s as though he’s vanished from Teyvat.

Zhongli worries. He spends his days going through the motions of his new mortal life, but always in the back of his mind is Childe, Childe, Childe.

One day the Traveler visits him, and shares a clue.

Aether’s directions take Zhongli to Konda Village, a quiet hamlet near Inazuma City where a young Snezhnayan by the name of Ajax has taken residence.

Ajax greets Zhongli with a smile that is friendly and nothing more. “Have we met?” he asks.

At his hip, his vision is gone. His shirt, simple spun wool, is buttoned all the way down and tucked conservatively into his pants. But that is not what stops Zhongli short. Not what leaves him open mouthed, stunned.

There is light in Ajax’s eyes.

His laugh is sweet as honey, lacking the dissonant, sinister note it once had. His smiles are pleasant, concealing nothing. His sharp edges are gone as though they never were, the darkness in his heart evaporated like dew.

He is no longer the man Zhongli knew, but he’s happy. He’s happy, and maybe that could be enough.

Zhongli lingers in the village, watching Ajax as he plays with children, fishes for his supper, and helps out in the fields. His blinding ambition, once bright as the sun, is entirely gone. In its place is simple contentment.

When the Traveler defeats the Shogun, Zhongli retrieves Ajax’s Vision from the statue. He feels the weight of it in his palm, and dreads the choice he must make. Is it merely selfishness to return it, to change simple, happy Ajax back to the vicious, ruthless man Zhongli loved?

Zhongli could never accept Ajax as he is, a man without a single scrap of malice, without the power and cunning he once possessed. Not when he knows and yearns for who Ajax used to be.

But Ajax is happy.

“You look like you’ve got something on your mind,” Ajax says to him, as evening falls over the quiet village and the Vision weighs heavy in Zhongli’s pocket.

Zhongli glances at him. “Are you happy, Ajax?”

“Sure,” Ajax says, with a friendly smile. “Are you, Zhongli?”

“I fear I am going to lose someone very dear to me.”

“I’m sorry. That sounds awful.” Ajax puts a gentle hand on Zhongli’s shoulder. “I’m here if you need to talk.”

“Thank you.” Zhongli brushes his fingers over Ajax’s. “It is well beyond time that I returned to Liyue. I wish you every happiness in the world.”

As he watches Zhongli leave, Ajax brushes his hand over his cheek and is surprised to find his face is wet. He doesn’t know why he’s crying, what deep sorrow within him broke open just briefly at Zhongli’s parting.

But it’s buried soon enough, and he returns to the warm lights of Konda Village where his humble life awaits.