lol that Sabrina artwork
Pretty sure these were fakes made awhile back by a japanese blogger. I remember seeing some fake snap cards as well.
Looks to be like a fan made event of some sort from the Japanese web page. Looks like they had a random table in the middle where different people brought in donated prizes. Only thing real I saw at first was some Southern Island 3 sets. They called it the “Old Back Festival”. (Had to read that a few times lol).
These are custom made (and thus fake) cards that serve as prizes for non-sanctioned tournaments under the umbrella name of “Old Back Festivals”. I went through the motions of scraping and translating that entire blog a couple of months ago because one of the cards had piqued my interest. I thought I had unearthed a never-before-seen old back trophy card, so you can imagine my disappointment was huge once I put all the pieces together!