Hiccup and Toothless are in the shop as well, Toothless having gotten in on the basis of being a service animal. It's not entirely untrue, given that Hiccup does have occasional mobility issues with his missing leg that Toothless does help with.

He picks up on Elsa's presence when she starts interrogating the attendant. That's not going to lead anywhere good, and the attendant really doesn't deserve it anyway.

"Hi," he says, approaching Elsa like she's a skittish dragon, while Toothless hangs back for a bit. "Look, I know you're a little freaked out right now, interdimensional travel can do that, but yelling at an employee isn't gonna help anything. She doesn't have any control over what goes on the shelves, she just works here."

Not for the first time, Hiccup's glad for his time as part of the Legion of Superheroes. Without it, he'd probably be as freaked out as Elsa. With it...it's all still pretty weird, but he at least has something approaching a good explanation.

"Look, do you maybe want to get something to drink or eat, and I can try to explain things? I can't promise helpful answers or even good ones, but I can at least promise something resembling them?"