A network card is much easier to obtain and much cheaper than any other card.
Yes, you can use a secondary NIC card. If multiple network cards are available, the PCI bus “parameters” of the one used for debugging must be passed to bcdedit upon configuring the target for debugging.
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5. If there is more than one network adapter in the target computer, use Device Manager to determine the PCI bus, device, and function numbers for the adapter you want to use for debugging. Then in an elevated Command Prompt window, enter the following command, where b, d, and f are the bus number, device number, and function number of the adapter:
bcdedit /set “{dbgsettings}” busparams b.d.f
6. Reboot the target computer.
https://msdn.microsoft.com/en-us/library/windows/hardware/hh439346(v=vs.85).aspx