It's possible, but it takes a bit of setting up - I do this with my own alarm system using my app AutomationManager available from play. When it reports an alarm it starts flashing the outside lights. You'd need to run AutomationManager on a dedicated device as a server, and you'll need a way to trigger it - ideally if your alarm system can make an HTTP post when it triggers, or if it can signal the alarm through an output, or via IFTTT (though anything that goes through the cloud is less reliable).

@JG07800 

 

The kasa app may not able to satisfy your needs; while you can verify whether the 3rd party programme can do that.

 

Like IFTTT, you can setup the alarm system as trigger and the smart plug as action, then control the bulb plugged into it. 

 

While to make it flashing, you may need do some research and take some time; or you can give it a go per Mike said. 

 

Good day.