After discussion, this might be promoted to a feature request.
Why do I need to manually add each device to the energy dashboard? Is there anything I'm missing here?
It would be easier to just auto detect devices which meet the conditions and exclude the entities you've set up as your grid / solar / battery entities.
The dashboard already prevents you from adding any entities without the required device class / measurement / LTS.
Alternatively, even an entity glob would make things easier, for example all my plugs would be covered by "sensor.stekker*energy" and "sensor.stekker*power".
Currently when I onboard a new device I tend to forget to also onboard them to the energy dashboard.