Favorite Strangers
Favorite Strangers by SpiritsFlame (AO3; multi-chaptered - 42,000 words)
Fandom: DC (film)/DC (comics)
Relationship: Bruce/Clark (indirect)
Summary: It's been six months since Bruce's actions led to the death of Superman. Six months, two weeks, four days. He could count it to the hour. He's handling it as well as could be expected when he finds himself in a Batcave that is unfamiliar to him, a world that is unfamiliar to him. Superman is still alive, Dick is still talking to him. The Justice League has been around for years, not months. And there is another Batman, who wants more answers than Bruce is willing to give.
When Batman v Superman!Bruce ends up in the comics world, he'll have to navigate another version of himself, his family and the man he tried to kill if he wants to get home.
Notes: i, admittedly, have very little vested interested in bruce/clark as a pairing, but this gets you by how it treats dceu batman as a real person dealing with trauma, and, worse than that, being confronted with how it could have been different. but it still ends with hope. lots of batfamily.