The strategy that I used to defeat another Order Empire is to spawn Swordwraith(and sometimes Archidon, not recommended) and attack full on when ever they spawn.
They key is to kill the miners. If more than 4 miners send some parts of the army to kill it, the other part will kill the enemy's army, but its unlikely to happen because you will need to keep on sending Swordwraith units whenever they are available. *Do not hold Swordwraith back to defend, send them to attack WHENEVER they spawn/or are available.
This strategy will not always work, but it is likely to.