Network stand-by should be in deed disabled by default in the normal configuration.
This means that the USB and RJ45 port are disabled so it should not matter for the on mode power measurement if they are connected or not.
We would however recommend to leave them connected to avoid any suspicion that they could draw any additional power when connected and not used.
It would be important to document this properly in the technical documentation.
Disclaimer: Please note that the European Commission cannot provide a legally binding interpretation of the EU legislation, as this is the sole competence of the European Court of Justice. Any remarks from the European Commission services are without prejudice to the position the Commission might take should related cases arise in a procedure before the Court of Justice.