@berkseo
yes, until now it has been implemented for rfm radios only, as nrf24 doesn't provide true rssi value. As usual, features appears along interests.
So if you want it for nrf5, maybe post/PR your snippet on github ;)
On my side no time for testing this, my mysensors HA isn't 2.4ghz based as I need longer range, and keep 2.4ghz bandwidth in case for others protocol (wifi, ble, zigbee) for limiting issues.