Ok. Sorry I can't help on this one. I've never done a native install of Linux on a Mac. But FWIW, VMware Fusion passes my WiFi connection through to the VM as a wired connection. Which you probably already knew anyway.
First thing, is that I have the opportunity to plug my MBP using ethernet, so I didn't need to download drivers onto a thumb drive but install directly.Anybody installed recent versions of Ubuntu Linux on their MBP 2017?