With a digital electric meter, I could read that out but I still have an old analog meter. But individually measuring devices is also appealing. HA allows for that. Opening the box would require an electrician and it only gives measurements per room or circuit. This may also be appealing to some.
I now look into ESP Home. I sadly didn’t found a clamp meter here that works outside the distribution box or require lose mains power but ESP has the option for clamp meters
Not Nextcloud. livesync is better. Requires CouchDB (Docker available) but with that, its a powerful sync option. Even Settings can be synced