Node-Red, RasperrbyPI and Adafruit RFM95W COMMS

Good day,

I have 2 RaspberryPis with a Lora RFM95X radio bonnet on each. I have succesfully got the communication going between the the radio/PIs. My question is how can I send data across between the two without pushing the buttons? Each PI will be connected to a pump and communicating to the pumps via MODBUS. I retrieve the pump state and faults and want to send pumpA details to pumpB and vica versa. Both PIs run node-red and would set the pumps to start/stop dependig on the other pump's status.

Any help would be appreciated.
Thank you