@Danny0xFF I put that exact request into the MKRWAN library a few days ago. Feature Request: Allow the MKRWAN library to send and receive very simple LoRa peer-to-peer commands · Issue #107 · arduino-libraries/MKRWAN · GitHub
What you want, can be done but it is very confusing and needs a linux computer you install a different board and directly manipulate the murata module using a github called grumpOldPizza. Hard to setup but once working is kind of fun. I agree that it would be best if the MKRWAN library could send LoRa.