VaranisArano wrote: »You can steal some clothing items, but they'll take up an armor slot.
You can use disguises like costumes as long as you don't lose the disguise. They can't be dyed. https://en.m.uesp.net/wiki/Online:Disguises
There are a few clothing costumes available from quests that might fit the bill for more clothing-like, less armor.
Merchant Lords’ Formal Regalia (quest ‘Forever Hold Your Peace‘, Thieves Guild)
Antiquarian’s Field Garb / Robes (Master Antiquarian Achievement , Greymoor)
Antiquarian’s Field Robes (Master of the Eye Achievement, Greymoor)
Master Field Cartographer (collecting Cartographer Fragments, Nchuthnkarst public dungeon, Greymoor)
Sixth House Robe (collecting 7 fragments in Forgotten Wastes Public Dungeon, Morrowind)