I know it's a bit old but this is the page as 1st result searching on Google as "SMOS WiFI".
Still wondering why everyone keep saying it's slower with wifi. I dont see any difference. Just connected with wifi connection and speed is same. I did 5 hours testing with LAN and WiFI. I know all stories but we're not talking about video streaming or something similar.

Conclusion is YES, it's possible to use SMOS with WiFi. Just some linux workout and having stable WiFi signal.