Crossbow Duelist (5e Feat)
From D&D Wiki
If you don’t have a hand free you can load a Hand Crossbow you are holding as a bonus action on your turn.
Light Crossbows you wield lose the Two-Handed property.
If a creature provokes an opportunity attack as a result of moving away from you, you can expend your reaction to make an attack against that creature with a loaded crossbow you are holding. You do not suffer disadvantage as a result of being within 5 feet of the target.