Hogsmead in Japan has this store but Wiseacre's Wizarding Equipment is only found in Diagon Alley in the U.S incarnations of Wizarding World (until 2016).
As for the additional alleyway in-between the Owl Post and Shrek 4D, like many of other members have predicted, is pretty much just a barrier to keep the the noise from that area of the park from spilling into the land. Don't expect an actual shop there. I think I mentioned awhile back that it wouldn't surprise me if they included an additional storefront that has some interactive wand elements . Seems like that will be the case with the "Brews and Stews Fishy Dinners" façade.