Tax Area Preference for VAT in EU

In EU we have a ship to that could receive product from a branch plant (same line of business company)  in Sweden or Germany.  The sales record needs to reflect the VAT tax area of the country shipping.  We have the tax area of the country of the primary branch plant in the ship to customer master and we are overwriting the tax area in the sales order if the alternate branch plant is shipping.  The obvious would be to add ship to's with the applicable tax areas, but we prefer not to set up multiple ship to's.  Has anyone else encountered