Nick,
thanks for the links!
I have now made one Heltec WiFi LoRa 32 V2 running but it is to bulky in size and it sucks up the battery in two days. (Maybe someone could guide me to a link where I can find (Using Arduino IDE) instructions how to reduce power consumption). And it is kind of expensive for the solution I have in mind.
My favorite would be a Raspberry Pi Pico solution - in combination with a RFM95W (as I am a big fan of Raspberry Pi). I have seen that the LMIC is supporting it. Any thoughts on that? I am a little bit heasitating as I am new to Pico.
Thanks
Eckhard