This Is USB-to-USB data transfer between two Linux OSes possible? question and the answer is USB 2.0 which is simply outdated. As USB 3.0 is much faster than simple Gigabit Ethernet and I want to connect a laptop and a desktop both with SSDs, this would be a great solution. If it's possible.
Is USB 3.0-to-USB 3.0 data transfer between two Linux OSes possible?
networking;usb
While this doesn't seem to be availabe, there are dual Gigabit Ethernet adapters (make sure to get a real dual NIC and not a NIC + switch) and that's 2GBit. Disappointing. Then it's down to bonding the two together. In my case, the desktop have spare PCI Express x1 ports so I will get a dual NIC card instead of converting USB 3.0 there. For the laptop, USB 3.0 expresscard (they make ones with practically disappearing ports) and an adapter seems to be the easiest. And since we are bonding, the laptop and the desktop both have gigabit Ethernet already so I can reach 3gbit/s theoretically which is quite good for syncing two machines which are limited by SATA speeds.