Custom projectiles

Im working on a data pack with a few others and we were looking to add custom projectiles similar to the trident where we can throw a weapon then pick it back up, we were initially going to use a trident as a base for this function but have been unable to remove/make the trident invisible is there a better way of making custom projectiles? We want the weapon to be a new model all together while keeping the base trident model and functionality.