Bright eyes

This story was so cool when I had my epiphany. After Bucky falls off the train, he wakes up and discovers that he's lost his left arm, has a head injury, and his speech system is impaired. Thankfully, Steve is there, taking care of him at his bedside.

It seems like they live in a villa in Brooklyn. Steve tells Bucky that he was unconscious until the end of World War II, and they received a large pension and bonuses (as WWII heroes), so their lives became more comfortable.

But one day, Bucky finds something in the room that couldn’t possibly belong to this era – a mobile phone.

Under Bucky's intense questioning, Steve reveals that he's from 70 years in the future. Or rather, they are currently in the future, 70 years ahead.

The universe split into this version, Universe 2631, because Bucky couldn't bear the nightmares and ultimately took his own life. He couldn’t handle the overwhelming guilt, and it nearly destroyed his mind and soul. Also, Iron Man didn’t die.

The one thing Steve can never forgive himself for is not searching for Bucky right after he fell into the valley, instead believing he was dead. So, Steve stops at nothing and goes back in time to save Bucky, bringing him back to the modern world. Stark Industries funds the creation of a 1930s-40s New York-Brooklyn town for Bucky, where Steve raises him.