The Ebony Scimitar cannot be purchased, and is only in the possession of High Ordinators (including Hands of Almalexia). At an enchant value of 80, this weapon has the highest enchant value of any non-stave weapon and the second highest enchant value of any weapon in the game. Some of them are pre-enchanted.
In the entire game (including all official expansions and plugins), the Goblin Sword has the highest maximum base damage of all short blades, unenchanted or enchanted, and the second-highest total damage potential with enchantment, but it requires very frequent repair. The closest to equivalence are: the light-weight, pre-enchanted Fang of Haynekhtnamet, which does 13–30 base damage (equivalent to 10–33 versus 10–35 for the Goblin Sword); and the unenchanted and 50% heavier Daedric Wakizashi, which does 10–30 base. If given the same Shock Damage enchantment as the Fang, the Goblin Sword cannot come close, having a highest minimum damage of only 16 (and range of just 16–17 in that case). The most powerful custom short blade in the game remains the Daedric Wakizashi, because of its high enchantment capacity, e.g. 20–58 in Shock Damage, even more with Fire or Frost Damage.) The Goblin Sword's maximum damage per blow (with Fire or Frost Damage 1–45) is 80, plus any Weakness to [effect], Strength, and other bonuses.
The Goblin Club has the highest maximum base damage of all unenchanted blunt weapons, and of all unenchanted one-handed weapons, in the entire game (including all official expansions and plugins). The only unenchanted weapons with a higher maximum base damage at all are the much heavier and two-handed Daedric Battle Axe and Warhammer. (Seven unique, pre-enchanted artifacts also have a higher max base damage: the hammer Sunder, the Mace of Aevar Stone-SingerBM, and the swords Chrysamere, Hopesfire, Trueflame, BiPolar Blade, and Gravedigger. Stendarr's Hammer would also qualify, but it is effectively unusable.)
The Goblin Club is also among the lightest high-damage weapons, and is surprisingly fast, given its awkward bulk. Its enchantability is, also surprisingly, on par with various Ebony and Adamantium weapons. The club's only down side is that it needs frequent repair.