To clarify: it concerns wireless Wi-Fi connections.
Thanks for the advice. A couple of questions, though...
To have a USB Wi-Fi adapter connect to the virtual machine with the result that my MacBook's Wi-Fi MAC address is bypassed: which system settings would it require? Moreover, USB Wi-Fi adapters, don't they have their own (and presumably static) MAC addresses? If correct: how to avoid that the Wi-Fi connection goes via the adapter's MAC address?