Business need Business unit dimension values to be forced on all accounts and in all transactions due the Business unit is primary reporting attribute. By using account structures, we can achieve this by making Business unit as mandatory financial on all main accounts. 

But in sales order and purchase order we need to split/Distribute the Accounts receivables and Accounts payables respectively as per the dimensions on each line of sales/purchase orders. 

For purchase orders and Accounts receivables free text invoices we can achieve this by updating the parameter in general ledger modules: 

Values used for summary account= Accounting distributions 

Gap is on Sales order; the above parameter will not distribute sales order header as per the sales order lines dimension. 

There is an existing Idea on this.

ideaid=408206bb-a643-ec11-a3ee-0003ff45ebbf