I have seen the following information a few different places, and it raises the question for me:
If the hand crossbow requires two hands to use--one for shooting, one for loading--then is there any benefit to using it over a two-handed crossbow?
You still need a free hand, so you can't use a shield or a second weapon, and you can always hold a two-handed crossbow in one hand while you grab something else or cast a spell.
Ammunition and Two-Handed errata
A couple of things that have basically been how I’ve been playing things, but good to see them officially in the rules. You need a hand free to reload a one-handed weapon with the Ammunition property. (It needs two hands). Also, although the maul and other two-handed weapons might require two hands to attack with, you can hold those weapons in a single hand.
This second clarification makes a spell-caster casting Somatic spells have an easier time with it when also wielding a two-handed weapon.