Assume that the hand crossbow is already loaded, you first use an action to attack with a net, then use your bonus action to fire your hand crossbow (and also reload it for next turn because you now have a hand free).
My only concern is (under special weapons on PHB p. 148) it says:
When you use an action, bonus action, or reaction
to attack with a net, you can make only one attack
regardless of the number of attacks you can
I take this to mean that if I had multiple attacks (such as a 5th level fighter) I could only take 1 attack with the net even though my attack action allows me more. In common sense you toss the net as your attack and don't have it to make multiple attacks. But this should not stop you from taking a bonus action to fire your hand crossbow.
Please use RAW whether you are confirming or denying the use of a net and hand crossbow in the same turn.