I want it to be little clips or flashbacks of Zen talking with his mentor and friend Tekhartha. All fond memories for the first part and teaching Zen about the Iris and all that.

Then when Widowmaker kills

Tekhartha, Zenyatta begins to unravel and lose himself day by day with grief only to be handed over a student, Genji.

He tries to decline as he is not fit to teach but another omnic says it will Genji major good to be taught their ways and who knows, maybe Zenyatta will find the peace he lost.

So he relents and takes in this stubborn and tormented soul, a nice training montage of failure at first that gradually gets better as it goes on and we can see Zenyatta laugh for the first since since Tekhartha’s death. He is bringing Genji the peace he needed and Genji, weither he knows it or not, ended up helping to save Zenyatta just as much as he did him..