I m not sure I understand your question.
You want the two xbee modules to have the same firmware versions? Am I right?
To form a network there should be one Coordinator. So in your case one module is Coordinator and the other one is Router. What is that you are looking for?
If you want to change the firmware of the module, follow the below steps,
- go to Modem Configuration tab, select proper Modem, Function set and Version
- click "Show Defaults"
- enable "Always Update Firmware" checkbox
- click "Write"
If "Action Required" window pop up, press the reset button on the development board.