Source: Player's Handbook

Prerequisite: Fighting Style Feature

While you're holding two weapons, when you hit a creature with both of your weapons before the start of your next turn, you can have that creature make a Constitution Saving Throw (DC = 8 + proficiency bonus + attack ability modifier). On a fail, they suffer one of the following conditions of your choice until the start of your next turn: Blinded, Prone, or Disoriented.