Why shouldn’t the EU build up a separate army from the EU states?
Any EU citizen could join if they get through the selection criteria. The general purpose would be wars in countries not complying with EU sanctions. It could consist of up to 1 million troops, several thousand military airplanes, several aircraft carrier groups and many frigates and destroyers and of course special forces. The EU Commission would be in charge but for longer wars would need authorization from the EU Council.