Motion or Alarm recordings would of course show us where and when something actually happened vs watching 3 days of video to check for an event. Not sure if this is possible, my install company kind of scratched their head when it came to alarms. Our old DiBos system had this, so I now miss this feature.
The sony cams are on the ONVIF list with "S" type compatibility. I saw in the forums ONVIF mentioned a lot as how alerts function. The QNAP site shows these cameras are compatible but alarm function is not supported. When you click on notes the qnap site says
I have alarms set up on 1 of our dome cameras and the SONY admin page shows the event getting fired with a green motion box.SONY SNC-EM600
This model support smart recoding & User defined multi streaming
not sure how up to date the site is for the compat list, but there are only 4 sony cams for 5.1. I am on the most current NVR Current firmware version: 5.1.1 for NVR
Date: 2017/06/07
I updated all the sony cams to the latest fw a few months ago when it was version 2.7.2.