How can i use the breaker power value to switch different devices

How can i use the breaker power value to switch different devices

you need to add other sonoff devices as widgets and then create a routine, then add it to the button #2 for instance and select when pressed turn off device X, when pressed again, turn on device X.

If I understood correctly your question, I hope this can help you.

currently not support using power value to trigger other actions, may I know why do you need this?
some power-monitoring devices have the over-load protecting settings, where you can set power/voltage limit to shut it down, this may help.