I think that will depend on if you plan on leveraging the RHACS Cloud Service (central hosted by RH) or the RHACS on OCP (central running on OCP).
Here are the traffic flows related to central to worry about:
I have a simple RHACS on OCP setup in my home lab. I used the "Network Graph" feature in RHACS to capture the flows in the namespace where my central is running.
Hopefully this may help you: