[The war had been raging for a long time now, and James Buchanan Barnes had been drafted some months ago to ship out to Europe and fight with all the others in the trenches and on the front lines. Telegrams came back daily with the news of more brothers, sons, fathers, and husbands killed. More friends who will never return, and still there was no end in sight.
But then something even stranger began happening on both sides of the timeline.
It was the result of Thanos trying to pull the time gem to him from where it was hidden on Earth, though nobody else knew that. It was just that the occasional object tended to disappear and then end up where it wasn't supposed to be, though only usually for a few moments or so before it returned. SHIELD, what was left of it, and the sorcerers worked to seal the issues and they managed to do it within only a few days. No major issues, no big anomalies in the past to muck things up.
But there was one piece of the future lost in the past that hadn't made it back.
The Winter Soldier-- Bucky-- whoever he was now, confused fragmented memories all he had to go on, had been thrown through time unceremoniously into a street that looked altogether familiar and confusing. He immediately went into hiding for a few hours, meaning he got missed when people tried to clean up the problems that the Infinity Stone had caused, but when nobody came for him by dusk he began to move again. His manner of dress was out of place now with jeans and a hooded sweatshirt, nobody else seemed to be wearing that sort of thing, but very few people stared. He didn't change it, he didn't have anything to change into. He found his feet taking him somewhere only half remembered.
An apartment with a key hidden under an old brick. Why did he know it was there?
He didn't know. He just let himself in, quiet as a whisper, and made his way through to the bedroom where someone was asleep under the covers. Skinny, blond, somehow also familiar (the man on the bridge? The man in the Potomac? The man at the museum? No, that didn't make sense, that man had bulging muscles, but somehow he was sure they were the same). He didn't say anything, just stood there and watched impassively, waiting for the man to wake up.]