This finely crafted dagger seems to be always shifting and exuding a faint dark smoke

You have a +1 bonus to Attack and Damage Rolls made with this weapon.
Whenever you throw this dagger and hit a hostile creature, you can force it to make a Wisdom saving throw of DC 15. On a fail, it is teleported to an unoccupied position of your choice you can see within 5 feet of you. Additionally, when you throw this dagger and don't hit any creature, you can teleport to an unoccupied position within 5 feet of where it struck. When you use either of these features, you can't do so again until you complete a long rest.
At the end of each of your turns, if it's not being held by another creature, you can make this dagger teleport to your hand.

This finely crafted curved greatsword shines a silver light that seems to expose the weak spots of it's enemies

When you strike a creature with Nightsilver, you curse the creature for 1 minute. The next time a 1 is rolled on the attack roll for a melee weapon attack targeting the cursed creature, the attack is a critical hit and the curse ends. You can only have one creature cursed by this blade at a time, when you apply the curse on a second creature, you remove it on the first.

This finely crafted blade shines an amber light that seems to impose the might of justice against it's enemies

When you strike a creature with ?, you curse the creature for 1 minute. The next time a melee weapon attack lands a critical strike against the cursed creature, the attack deals an extra die of weapon damage and the curse ends. You can only have one creature cursed by this blade at a time, when you apply the curse on a second creature, you remove it on the first.