You would need an umpire and some march rules. It is my understanding it is not too much work to design a custom scenario if one already has the oob and map.. If this is not true then forget I mentioned it.

The idea is the intial dispositions are unknown to the opposing teams. They issue march orders and the umpire determines where the fight will be and makes the scenario. They fight, new orders issued, casualties carry over..lather, rinse, repeat.
Seems like you would need to make it a what-if scenario for balance....and limit the force sizes somewhat.
Maybe 1 or 2 Corps each side. Orders issued in a roll-play fashion..beards not required. Anyway..just an idea.