Good point. I didn't see behind the text without opening a bigger image. The article mentioned it was drawn so the front and back image stacked for the full picture. When you look at it from that perspective it could also be regular sephiroth holding something up between the two of them.

Regardless though I gotta take it with a grain of salt. Someone on the design team back before the first remake launched said to pay close attention to the game's key art and we'd find something interesting. If I recall it was only a black feather or some other mundane feature that didn't reveal anything spectacular even after playing the game. It was just marketing to get people talking.

I can't help but think this is similar. Fun stuff to think about while waiting for the game but probably won't amount to much even when we've seen the final product. I'd love to be wrong though and this is actually hiding a new twist. Time will tell.