[Edi]

If we're talking about the independent militia units (the worst of which is the default for the militia event and is also included in some national rosters, e.g. MA Arco), the hoburgs will kill them every time.

The reason is that the hoburgs have high defense and pack six into a square, meaning that any given square of size 2 militia is going to be outnumbered two to one when going head to head and the indie militia's low defense means they get hit a lot. And as they take damage, morale checks will spell doom for you because militia has really crappy morale.