What if Bruce was thrown into an AU where his parents are alive, he has a wife, he's not batman but the JL is still a thing and the batkids don't exist.
Just imagine how furious he would be when he can't find his children, HIS CHILDREN. yes he has his parents back but what good does that do when he can't show them his children. His most valuable think in the entire world is gone, and he is furious about it.
Also just him seeing how shitty Gotham is doing without her Protectors, her Knight.
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Cut to Bruce trying to convince the JL to help him get home, cuz he has no Batcave and no armor
Hal: So you're saying that, you, YOU, billionaire Bruce Wayne willingly dresses up as a bat to fight crime at night, in the most dangerous and cursed city in the entire world. Yeah not buying that
Bruce:...
Wife: Brucie baby, are you sure you're okay?
Thomas: Son, I really think you need a hospital
Martha: My poor baby
Bruce: your real name is Hal Jordan, Flash's name is Barry Allen, Superman's name is Clark Kent, Green Arrow is Oliver queen and his wife is the Black Canary, do you want me to go on or are you fools going to help me get home to my kids!