It took some time, but I managed to run an example of LoRaWAN with STM32CubeIDE + STM32CubeProgrammer. Data gets sent to the gateway.
But I’m not able to get the module into low power mode (few uA), it still consumes 1.3mA while sleeping between sending data. I believe it is done here: RtcEnterLowPowerStopMode().
Did anyone manage to get into low power mode? I managed to find some example from ST.COM page, but it uses ~200 LOC to get into low power mode. Have not tested it yet and not sure if simple copy/paste will work here.