The same name can be used for multiple entities if they are part of different modules. When all of them are added to the same project version, you must prefix them with the module name while invoking the service.
In the example below, 3 Modules have entities with the name Order. The metadata will tell you the exact name to be used while invoking the service.
https://hubwayconnect.com/HW/rest/odata/product-sales/$metadata
<Schema xmlns="http://docs.oasis-open.org/odata/ns/edm">
<EntityContainer Name="Container">
<EntitySet Name="OSAcc_Opportunity_CS_Order" EntityType="OSAcc_Opportunity_CS.Order"/>
<EntitySet Name="OrderManagement_CS_Order" EntityType="OrderManagement_CS.Order"/>
<EntitySet Name="NorthwindDB_Order" EntityType="NorthwindDB.Order"/>
</EntityContainer>
</Schema>
The names highlighted above should be used as Entity Names while invoking the service.
For example:
https://hubwayconnect.com/HW/rest/odata/product-sales/OSAcc_Opportunity_CS.Order
https://hubwayconnect.com/HW/rest/odata/product-sales/OrderManagement_CS.Order
https://hubwayconnect.com/HW/rest/odata/product-sales/NorthwindDB.Order