Bucky knew he'd changed. He remembered the way he used to be, before everything that happened during and after the war. Had this been the 1940's and he'd shown up, obviously, he would've just gone right up to Steve, wrapped an arm around his shoulders and started talking about this or that without batting an eyelash. It would've been easy as breathing. He'd regained a lot of what he lost, but that -- that carefree part of his personality was still lost in translation. He had his humor, his wit, his ability to converse about most thing (that one, he just often chose not to engage in unless he was with a very select few people) but understandably so, he just wasn't the man he used to be. Steve was one of the few people who got that, thankfully, even though he was also the driving force behind his motivation to believe he could still be Bucky, not just what was left of him.
He nodded to Steve's response, and drew in a breath as the other man moved closer. In the world he'd been ripped out of, he'd only seen Steve a short while before and was actually on his way to see him again before they stepped foot on the battlefield, but something in his heart told him Steve was really needing the hug they both naturally stepped into. That became almost painfully clear in the way Steve tapped into a bit of that strength the serum gave him. Bucky returned it, just as fiercely because it seemed like it was very important to his best friend to know that Bucky was truly there.
That didn't bode well for whatever point in time Steve had been pulled from. As they drew back, he kept a comforting hand on his friend's back and met his eyes; Steve was still one of the few he actually could make eye contact with and hold it. "Is it bad for me to say I'm glad you're here? Even though we shouldn't be here, and we don't know what exactly 'here' is?"