Sure, it’s all the same idea.
You set a condition so that event A ( The trigger) sends a message to the hub and then the hub sends a message to another device (the target) to do something.
Once you have that, you can set up all kinds of logic in smartthings that affects whether or not the message actually gets sent to the target.
So in this case, the trigger event would be the door sensor detects the door opening. The target would be turning off the smart switch that the power out alert device is plugged into.
You just need to set some conditions on that automation so that if you’ve pushed the button, the message doesn’t get sent to turn the smart switch off.
You could do that with modes, or you could do it with an “and” condition, it just depends on whether you’re willing to use custom code, whether you’re willing to use a $10 third-party app ( and in that case, what kind of phone you have), stuff like that.
See the following FAQ (the topic title is a clickable link)
And then if you still need help, just ask and there will be lots of people will be glad to help depending on the parameters I just mentioned. 
( you could also just physically unplug the Power out alert device and then plug it back in later if yours is a household that would remember to do that. )