Unable to assign the cost object of another company code in the cost assignment of expense report.
For example, Employee who belongs company code 5000, when trying to assign cost object(Sales Order or Internal Order) which belongs to company code 6000, its giving an error saying" cost assignment missing" and cost assignment to sales order is being accepted.
First you need to confirm that intercompany processes are activated within scoping.
Second, confirm if staffing list is maintained on the cost object. The staffing list is optional but if it is maintained, then make sure the employee is maintained in the staffing list.
Third, confirm if company code list is maintained on the cost object. The company code list is optional but if it is maintained, then make sure the employee's company code is maintained in the company code list.
I'm interested to hear if this helps you since it's fairly new functionality. Your experience will assist many who will follow you.