Anushtegin
Sergeant
Yes,my mercenaries that spawn in imperial taverns have heavy nord/sturgian infantry called "guards" that are inspired by the varangians.Incidentally since they are nord/sturgian they can branch off and loop back into the Nord tree and become huscarls.
Nothing ruins your day like seing an heavily armored axe wielding nord charging at you while fighting imperials. Expecially when the guy who just axed you is your own creation.
EDIT:also, to clarify, lords will hire only stuff they see as upgrades of the mercenary_1 unit, meaning the watchmen. They don't seem to hire armed traders. The way I make the hire my troops is by making my basic mercenaries "fake" upgrades of the watchmen. I say fake because those upgrades require an un-obtainable custom item. This way the game "sees" all of my troops as part of the possible upgrade pool for the watchmen and since the tavern can spawn the watchmen OR any of the upgrades, my mercs will spawn.
Furthermore, the AI seems to hire from the taverns only after they hire from the notables and given that any of my mercs can spawn they might not be able to afford them. The game auto-calculates the cost of mercs based on their level and their mount. So if the tavern rolls some tier 5 cavalry they may only be able to hire on or 2 troops.
armed traders aren't worth it anyways, because for soem reason the caravan guard line troops don't seem to upgrade to better caravan guards.