to memory now I can't recall (слэш)

While on a mission storming a HYDRA facility, James Buchanan Barnes touches one of the many strange alien devices collected by the Red Skull. He does this, in fact, twice— in the past, and in the future.
Next thing he knows, Bucky Barnes is opening his eyes in the 21st century, which is full of great gadgets and coffee, and at least includes his old pal Steve. (And, inexplicably, a different Stark.) Meanwhile, the Winter Soldier finds himself in the middle of World War Two, helping Captain America hunt down HYDRA (which is at least familiar), pretending to be Bucky Barnes (which is not), and figuring out the very noisy group of soldiers who call themselves the Howling Commandos.