I converted my cable park to a USB-C cable (male to male) and lots of adapers (the short sort you can keep in a box) years ago. Yet i have still some devices with a mini-B female port.
Only thing i found online are cables and everything else. Heck, there's even mini-DP > C and ethernet > C in that form factor.
To clarify, i look for something like this but mini-B instead of micro.
edit: Region is Swiss, Europe.
editedit: thanks guys, found one.
The USB-C (female) adapters are hard to find due to technically being non-compliant. If you're interested about the reasons and some further context, I can recommend this article: https://hackaday.com/2022/12/27/all-about-usb-c-illegal-adapters/
In your specific case, it's twice as hard to find such an adapter due to MiniUSB being so uncommon these days.
Ah, so that's why the C to micro adapter to charge my old Galaxy S3 only works one side.
That's a very interesting article, thanks!