I noticed something interesting if you give a follower forsworn weapons (such as Jenassa forsworn swords.) They will dual wield in combat.

They do it anyways. I tend to give them a bunch of staffs. They will equip then randomly and dual wield them. I also give them a number of differnt weapons too all with soul capture and a bunch of soul gems.

Stupid phone. I didn't know dual was spelt as field

Thats staves which is different, I've never seen a follower dual wield swords, axes or maces. Give a follower two forsworn weapons and they'd duel wield the blades.

I have mine doing it with any one handed weapon I give them. So long as they have one handed skills. Had jordis dual ebony axes with soul capture fire/ ice enchants on them.

Jennessa will dual wield anything, but the db people will only do it with the forsworn weapons as well as a few others.

Jordis never puts down her shield for me

I've tried with Jennessa and she doesn't dual wield say steel longswords she'll only draw one, neither did jordis. But when I give a one-handed follower two forsworn weapons they will dual wield them.

Hmm..... I seem to remember having her dual wield glass swords, may be mistaken though

I'm also using a mod that removes her basic gear from all followers. So that helps. ￡:

But anyways. If you have a follower that does not use 2 handed or sheilds or bows they will dual weild eventually

It's not 100% of the time sadly. I never give my companions forsworn/falmer/daedric gear though.

Try putting on an Amulet of Mara.

Jenassas may not seem to dual wield at first, but it becomes her norm after a few fights. Got her two scimitars from some pirates by Solitude.