You can use WMWifiRouter : http://www.wmwifirouter.com/
It has one mode that allows what you're looking for.
You just have to add your WiFi as your default WiFi node on WiMo. WMWiFirouter will use it.
PC -> USB cable -> phone (HD2 in my case) -> WMWifiRouter -> WiFi -> WiFi Hotspot (WiFi router in your case) -> internet.
Using it to write down this post.
Hope it helps !
Galaxy Note 2 - N7102
(dual active sim, dual standby)
- Stock ROM
Samsung Captivate Glide
- I927UCLG9 - 4.0.4 ICS - "Official" Leak
HTC Rhodium (Touch Pro 2
) - WiMo - ROM : 1.86.406.1 FRE, Radio : 126.96.36.199