The visibility for intercompany invoice in Sales Order Screen (ActionsàAdditional Order Info) is available for only Internal Sales order. For Regular Sales Order when shipping (US) and selling (ES) organization are different legal entities (different OU) the intercompany invoices did created but it displays only Customer invoice in Sales Order Screen (ActionsàAdditional Order Info) not intercompany invoices. Inter-Company AP invoice will be visible in the payables and the Inter-company AR Invoice will be visible in the Receivables responsibility respectively.
According to oracle, we can view intercompany invoices for internal sales orders on the sales orders window (Actions > View Additional Line/Order Info > Invoices / Credit Memos) by setting profile option OM: View Intercompany AR Invoices profile option: Yes.
But it’s not possible to view the intercompany invoices for regular sales order.