Not putting them in their inventory (Equip them stuff like weapons or amour)
No. You can drop things, or knock them out and put them in their inventory, but you can’t force them to put clothes on. Not without editing files. I know in the beta if they had a weapon in their inventory, even if you are the one that gave it to them, they would use it if they got into combat. I haven’t tested that on the live version.