I have no idea if they're from the same magazine or not (I think so since the seller is selling another couple of posters with Angel&Buffy and Angel&Cordy that look like they're a pair since Buffy's shoulder is a part of the Angel&Cordy poster) I just now that I have to buy them (they're on a Swedish auction site) and display them next to each other.
I wonder if the artist realized that's what they said, or if it's accidental. I like to think he/she is a slash-shipper. :D
Here's the posters (when the auctions finishes they will eventually disapear).