Aqara Smoke Detectors are not linked directly but using the Aqara-Hub or any other SmartHome System.
Here is my approach to this problem. I went a little overboard with this:
Self-Test walk-through of all detectors using notifications
Smoke-Alarm / Fake fire alarm test
Smoke-Alarm pre-notification for false alarm prevention
Mute alarm
Persistent Fire-Alarm notification
Customizable Text-to-Speech notification for Android (iOS not tested)
Customizable notifications
Actions on alarm
Wakeup detectors on test and alarm
There are still some things on my todo list but this blueprint is ready for use.
This blueprint only works with Zigbee2mqtt and exactly these smoke detectors.
You can find the 
Aqara Smoke Detector linker for test and alarm blueprint on my github account and also the Import-Link, documentation and issue tracking there. Please the information on that page and of the blueprint after import carefully. There are plenty configuration option and warnings.
In addition I recommend the Aqara Smoke Detector Keep-Alive blueprint, because these battery devices have a deep-sleep mode that causes long latencies when reacting to commands. This will compensate for this.
I was inspired by @vansummeren “Aqara smoke detector linkage alarm plus optional actions”, @ciB “Aqara smoke detector linkage alarm” and @saint who created a keep-alive automation. It is not my intention to undermine their work but when starting to look at it I noticed some bugs that lead to a total rewrite.