Installation of one or two electricity meters?

Unfortunately, there is no cheap heating electricity in our town, and I want to transfer my EON electricity contract, which I concluded at Media Markt with 30 cents/kWh, to the new house and use it to settle the house and heating electricity.

Is it really that simple?
We also wanted to do that with our cheap electricity contract from the previous house.
However, our provider replied to the inquiry about whether we could take our contract to the new residence, essentially with "Goodbye, you idiots."

Here are the DHW settings and the heating curve:





I still can't explain where the increased DHW consumption is coming from.
Anyone have an idea?

Best regards