Dear all,
I am working on this case from a while now and didn't find a solution (except disable the responder alerts in Project Settings, something that a don't want to).
Actually, with the above setting enable, whenever someone is assign to an incident, the field responder is automatically fill with the value of the assignee and an alert raised in opsgenie regardless the priority of the incident. I havent any automation that make an intervention in this process and aren't able (after many tries in opsgenie option integrations) to solve that case.
In our use case, we only use the opsgenie alert for P1 escalation. So I don't want that when someone is assigned to an incident the responder field is automatically fill and an alert is raised in opsgenie regardless the incident priority. We only have an automation to fill the responder field with the correct opgenie team when a P1 is detected.
Have you ever had a similar case and misfunction, is it a "standard" behavior when the "RESPONDER ALERTS" is enable ?
Thanking you in advance for your help and knowledge sharing regarding this case. 
Django