Bawylie
A very OK person
I agree with everyone who says just to treat it like a spear.
But if that doesn’t work, consider a battle master maneuver specifically for the shield throw. If you have additional attacks, it can ricochet between opponents. If all the attacks hit, it bounces back to you, but if any miss, you’ll have to go retrieve it. You get the extra damage from the battle master die and maybe keep the shield bonus to AC for using the maneuver.
But if that doesn’t work, consider a battle master maneuver specifically for the shield throw. If you have additional attacks, it can ricochet between opponents. If all the attacks hit, it bounces back to you, but if any miss, you’ll have to go retrieve it. You get the extra damage from the battle master die and maybe keep the shield bonus to AC for using the maneuver.