This idea came to my mind already some time ago. I bought some "Smart Plugs" and I flashed them with Tasmota firmware. It allowed me to overview and control powert usage. One problem - each plug was separate. That is the main reason I decided to launch this project.
You need some PC or similar device to run Java application. You need plugs with Tasmota firmware, where the host is configured to Java application mentioned above.
To be continued...