[Endoperez]

Well, adding magic item to a recruitable only adds the weapon or armor, and none of its properties. So that is out.

It might be possible to add a weapon that horrormarks everyone on AoE1, but then those commanders would just be kept far from melee if they still had their original weapon.

However, I don't remember ANY unit that starts with Horror Marked, so I don't believe Illwinter has made that avalable to modders.