Issue has been send and handled by support now and is a known issue that will normaly be solved in mendix studio pro 9.8.
This seems to be an issue that you could contact Mendix support about.
With the latest release of Mendix Studio Pro (9.8.1), It can register Entity as ODATA in Datahub without any issue. But, it looks like only Read and Update are enabled. Still Create and Delete shows disbaled.