@EricBr 

No tool to do that. 

Best you can do is put two computers side by side with a router attached to each. Then go through the settings, especially good is you have reserved addresses, port forwarding, and such where you need to transfer MAC addresses and port numbers.

You connect one of the routers direct to a PC via Ethernet which it off line and use your router;s IP address such as 192.168.0.1 

  @ArcherC8 

Thanks, that's what I was afraid of.

Thanks again,

Eric