Im not quite sure what it is u are looking for, so Ill tell u what I know. Most weapons acquired on lower levels will slow down attack speed like Hack, because the item level is higher than you tho u can equipt it. This value will decrease as u level up or get the 'skill': sword lore (which increases attack speed and damage, while lowering the penalty u suffer from high level weapons). U can notice it with armors too, that high level armors will slow you're overal movement speed (this too decreases and then disappears altogether when you're level is high enough, u can limit and even remove this penalty with the 'armor' skill (which reduces a the movement slow penalty on armor pieces, which can stack, and also increase you're overal armor).
In short high level sword like Hack on early game = -% attack speed due to you're lower level compared to the level of the sword
(IF the same occurs with bows ull need ranged combat, for spears/staves ull need long handled weapons, for axes ull need axe lore etc.
To counter it: level up or get sword lore skill
Same with armors of higher level = -% movement speed
To counter: level up or get armor skill