This question is incredibly stupid but I am still not sure about this feature despite having like 25 hours spent in a game.

 

...Interrupt value different for individual weapon types (0.5s, 0.75s etc) is a time of interrupt which happens when you hit and ENEMY with this weapon, or a tme of interrupt happening to YOU when enemy hits you while you wield this weapon?

 

My idiocy led me to believe there are contradictory statements in-game about that.

The listed interrupt value is applied to the target being struck by the weapon or spell.