USB to USB Networking using USBNET Cable
First and foremost this has nothing to do with USB On-the-Go which some devices support and has nothing to do with Pi Zero "Gadget" Mode....
USBNET Cables have a Chipset to enable negotiation of USB Host / Slave Mode so there is no danger of blowing the USB Port Chipsets.
It has been suggested Belkin & Plugable both use a Prolific PL-25A1 Chipset:
The following is a non exhaustive list of various which supposedly use the PL-25A1 Chipset:
https://www.ebay.co.uk/sch/i.html?_from ... 8&_sacat=0
https://www.ebay.com/sch/i.html?_from=R ... 8&_sacat=0
https://www.amazon.co.uk/Plugable-Trans ... B005OTPVMY
http://www.amazon.com/Belkin-Transfer-C ... B0093HCIQ0
https://www.amazon.com/Plugable-Transfe ... B005OTPVMY
https://www.amazon.com/Belkin-Transfer- ... B000JJPZW0
These type of Cables are quite often sold as "Microsoft USB Easy Transfer Cables" and cost around £20 / $25 but are not very popular so searching etailers to achieve best price is recommended, though be aware not all will work, I had a Un-branded (Prolific PL-2501 Chipset) Cable which states "Bridge Cable" and is not recognized as a Network Interface ln Linux
Linux USBNET http://www.linux-usb.org/usbnet web page is out-of-date but has some good information ( It would appear any recent release of Linux based OSes can support USBNET ).
My x86 PC was running Xubuntu 18.04LTS and supports USBNET Networking by default so was able to enable "internet connection sharing" ( please note I do not have Windows or MacOS Machines )....
.....my Pi 2B automatically recognized the connection under Raspbian Buster.
Previously also had a RPi Zero as well as running Raspbian Jessie, Wheezy and Stretch, the current Raspbian Buster on my RPi 2B shows similar results to below
Updated August 2019