When you attack with your Hammer, you deal 1d4 + your attack modifier bludgeoning damage. As both weapons have the Light property, you can use your bonus action to make an attack with your off-hand Sickle for 1d4 slashing damage, but you do not add your ability modifier to the damage unless you have the Two-Weapon Fighting class feature.
When you attack with your Hammer, you deal 1d4 + your attack modifier bludgeoning damage. As both weapons have the Light property, you can use your bonus action to make an attack with your off-hand Sickle for 1d4 slashing damage, but you do not add your ability modifier to the damage unless you have the Two-Weapon Fighting class feature.