I know that wifi servers for City Folk are long gone and that the only known way to play multiplayer involves hacking which we can't discuss here but an idea popped into my mind and I want to know if it would work.
If myself and a friend were to connect both of our Nintendo Wiis to my wifi network, would we be able to play in each other's towns despite the servers being down? I've never tried this but would it be possible? Thanks in advance and have a nice day!
The idea you described is known as "LAN", and is actually a common way to play games. If everyone is on the same network, especially if they're using cables versus wireless, then it's the fastest way to play PC games multiplayer.
Unfortunately, AC:CF, Mario Kart, etc., do not support LAN on the Wii. Those games all point to a specific set of servers in order to initiate the matchmaking/friends list/etc., and, as we all know, those servers are no longer operational.