1) The first story has Derek owning a supernatural shop that has protections so humans don't casually wander in. That doesn't seem to stop Stiles from finding it though, as he keeps coming in and coming back much to Derek's annoyance. It turns out Stiles is a spark which gives Derek a "so that's how he did it!" moment. I believe it's Sterek.
2) The 2nd is a series. It starts with during a fight Stiles magically disappears in front of Derek from the woods in Beacon Hills and reappears in New York years earlier to a younger Laura and Derek. Stiles gets training from a supernatural being who owns a bookstore, so prepare for the future fight he knows is coming. So when he disappears he will reappear shortly after but much more prepared. It was Sterek definitely.