I ordered the below since it says the internal size is up to 3" x 3", similar to the PlayDate. But, I haven't received it yet or my PlayDate so can't offer any further comments.

https://www.amazon.com/gp/product/B08WZCFH8L/

Can be found at the links below. No affiliation at all with this company.

https://www.amazon.com/gp/product/B08WZCFH8L/

https://casematix.com/products/casematix-protective-travel-case-compatible-with-magsafe-duo-charger-and-cable-hard-shell-carrier-with-wrist-strap-and-reinforced-zipper-case-only