Can’t help you there definitively Omahanime.
I do have some Dungeons and Dragons cards that are rounded and some are squared off. They were cut at Wizards of the Coast too.
The explanation I got at the time with the Pokemon (1999) was they were part of an alignment process. Probably done through programming a computer? But I don’t have first hand knowledge of the process.
Glenn may have some knowledge with this he can help you with.
updated the first post. I do own a square cut blastoise. Regardless of how it was cut it’s still a really nice piece to put into my blastoise collection.
I hope it’s good condition because it looks lime the blastoisr is no where to be found in the last 3 years I’m very happy that the set I’m getting has the blastoise in the best condish