The male to male cable to transfer between machines probably has a device with two slave ports in it. There's EE reasons, as well as protocol reasons why just plugging two hosts into each other is a bad idea (and fixing that was most of the work behind USB OTG).

Female to female is fine, because there shouldn't be a host with a male end that isn't OTG.

And beyond that, there totally exist the banned adapters (C female to A male) but that has more to do with the fact that you can get anything from China, regardless of trademark infringement.