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.
This thread made me realise how awesome it would be to have a specialized search engine or storefront where you can describe a custom bit of cabling or donglage based on what you need to connect together and search whether anything like that exists.
Even more awesome if it could find the cheapest adapter chain in the case where it doesn't have it directly