[google-appengine] is there a way to connect App Engine (standard) to a Compute Engine instance without going through the external IP address?

The docs say "You can use sockets to connect Google App Engine apps to Google Compute Engine instances." Is the limitation still that it can't communicate on the same network and must go through the external IP of the compute engine instance? Can app engine Felxible connect to the internal ip ad

Re: [google-appengine] is there a way to connect App Engine (standard) to a Compute Engine instance without going through the external IP address?

Flexible runtime app instances exist within the same network resources as GCE instances, because they are GCE instances. In that way, the GAE Flexible instance can be configured to run in any existing network resource and communicate to other instances using the local IP or hostname. For Standard