Yes you have live data - You have to set yourself a Modbus address (the inverters can only be address 1) so set yourself somthing like address 10.
Modbus is a shared bus - so you can continually poll the inverter (say every 10 seconds) - occasionally you will get a collision with the WIFI dongle but they will both recover.
The WIFI dongle will continue to do its thing and send data to the cloud and you can log all your data locally.
Craig