It is possible to upload from Mervis IDE to PLC:
Axon
Neuron
Unipi 1.1
Extension
Solution configuration includes:
Hit Deploy solution on the Ribbon and select which parts of this configuration (Program, HMI,..) you want to upload and to which PLCs
Each of the IOs can have its own configuration settings. Those are:
This configuration isn't uploaded by deploying solution and you can read about the process here
RT configuration upload includes:
This configuration is not uploaded to the PLC via Deploy solution. Check this tutorial for additional info.