The weapons in Hyrule Warriors: Definitive Edition can contain different elements and the only characters who can use twin Light/Darkness weapons include the Triforce wielders. Midna from Twilight Princess is also counted among these characters, as she briefly held the Triforce of Wisdom.
There are five different elements in Hyrule Warriors: Definitive Edition that are attacked to different weapons - Fire, Water, Lightning, Light, and Darkness. The Darkness element deals more damage if the player repeatedly attacks the same foe. while the Light element deals more damage if the player attacks a group of enemies.
There are only four weapons in Hyrule Warriors: Definitive Edition that use both the Darkness and Light elements together - the Darkmagic Sword, the Darklight Mirror, the Gloomy Rapier, and the Swords of Renewal. These are some of the strongest weapons in the game and three of them belong to the classic wielders of the Triforce from throughout the series. The Darkmagic Sword is used by Link (bearer of the Triforce of Courage), the Gloomy Rapier is used by Princess Zelda (bearer of the Triforce of Wisdom), and the Swords of Renewal are used by Ganondorf (bearer of the Triforce of Power).
The fourth weapon is the Darklight Mirror used by Midna. As pointed out by the Gaming Detail Reddit, the reason why Midna is also given a Darkness/Light weapon is that she also held the Triforce of Wisdom during the events of Twilight Princess, as Princess Zelda transfers her soul into Midna’s body, presumably bringing the piece of the Triforce with her.
There have only been a handful of Triforce wielders in The Legend of Zelda universe and they never stay out of the hands of Link/Ganondorf/Princess Zelda for long. The creators of the series have discussed how the relationship between the three Triforce users is a core part of the story and we’re unlikely to see any shakeups in the formula in the future. Midna only carried the Triforce of Wisdom for a brief period of time, but the creators of Hyrule Warriors: Definitive Edition still decided to include a reference to her role in the game.