We know, thanks to the DMG, that a creature has disadvantage with a weapon sized larger than itself, but the wording is less clear concerning the damage. My reading is that the increased damage is considered (mechanically at least) to be due to the weapon being oversized, rather than the wielder, but I would like some second opinions. (RAW and RAI interpretations both welcome)
So, would a medium sized creature, specifically a Monk PC, wielding an oversized (large) spear deal 2d6 damage on a successful hit? Furthermore, would a large creature with a huge spear deal 3d6? Etc, etc, etc.