I was curious if I was to enchant my ally's weapon to fill soul gems and gave them empty soul gems if they would get filled by them. I wanted to ask first before I wasted the enchantment on their weapon.

Thanks

i never tried it lol good idea

Yes, your follower will fill soul gems if you give them empty soul gems and soul trap weapons. There is a bug so that sometimes they will fill a whole stack of soul gems of at once. It happened to me a few times, but I couldn't figure out how to trigger it consistently.