The Apple Watch already can and does use WiFi and will connect to existing configured access points:
http://www.iphonehacks.com/2015/05/how-to-ensure-apple-watch...
Presumably if you tethered your personal phone to a second phone, then the apple watch could and would also connect directly to that second phone's WiFi hotspot without your personal phone present.
The Apple Watch already can and does use WiFi and will connect to existing configured access points:
http://www.iphonehacks.com/2015/05/how-to-ensure-apple-watch...
Presumably if you tethered your personal phone to a second phone, then the apple watch could and would also connect directly to that second phone's WiFi hotspot without your personal phone present.