Thanks for the reply, RabidGears. Yes, sorry for being clear as mud! To test, I did add a perk to an actor in the game, which did fire the contact spell when the NPC having the perk hit another NPC, causing the NPC to drop his weapon and fall to the ground, as I wanted. But I don't want to do this to every actor. It would take too much time and cause conflicts with mods that change NPCs.
But when I try to add a constant effect spell to the Nord race, with a magic effect that applies a perk, which in turn fires a contact spell on hit, the game does add the perk to the player character, but doesn't add the perk to any other character having the Nord race.
From what I've read after starting this discussion, dynamically adding a perk to any character but the player always fails. So now I'm looking for an alternative way to get NPCs to use a spell that fires on hit, since I can't use a spell or script to add a perk that accomplishes this.