I have one almost similar to your request l use but unfortunately l did not buy it here in Zim. I got it from alibaba.dot.com.
The way it can be connected is that the dongle can connect to it on the usb slot, then the pc can connect on the cat 5 socket and get internet. At the same time 7 devices can get wireless connection at the same time.
It can draw power from usb port on pc or power source. It has a battery when on the move it used to give me 4hrs. Thats when l was using powertel modem.
Bt now since lm using telone adsl, l use it jus as a wireless AP