They are stacks and stacks of counterfeit cards.
This guide will be of help:
www.elitefourum.com/t/carddass-pocket-monsters-pokemon-anime-collection/29374/1
They are not my childhood cards. They are cards from a business that I owned in 1998 and 1999. They were purchased from a vendor directly. I sold a large amount of pocket monster items from Japan as well as being an official Sanrio dealer. I know that they came directly from Japan and that I purchased them in either 1998 or 1999. They are vending stickers not cards.
Well, if you sold a lot of those vending stickers, then you sold a lot of fakes. Because the ones in your picture are counterfeits.
Ah yes, the yellow Gengar we all know and love…
Yep. And the Chansey kana flash card that has been turned into a prism sticker. 