Kate & Peter
"...Wait, what?" Peter blinked at Kate, trying to process what she'd just said. But then again, her knowing another Peter wasn't out of the realm of possibility - people ended up here from different points in time, even different dimensions. "Sorry, it's really nice to meet you too - but what?"
Peter didn't know how old Clint exactly was these days, but he was old enough to have a family, apparently, and to be settled down. That felt like decades away from where he was now. "Are you sure we're the same guy?" Well, same-ish, depending on what universe Kate was from. "Did you come here from the future?"