Hi @siva-subramanian
When using the Edge Server API, qaMode doesn’t behave the same way as with the Delivery API. Even if you pass the QA parameters, the Edge API continues to evaluate audiences (like ECID) in real time instead of forcing the QA experience defined in the link.
At present, full QA/preview functionality is only supported with the Delivery API and Target server-side SDKs. With the Edge API this is a limitation, so if you rely on QA mode you may need to test with Delivery API or submit a feature request to Adobe for Edge support.