Nope. Ninjutsu says that you return an unblocked attacker you control to [its owner's] hand as part of the cost of activating the ability, if Smuggler's Copter is an unblocked attacker it qualifies.
August 3, 2018 4:26 p.m. Edited.
No special rules. If you're attacking with Smuggler's Copter (in which case it has to be a creature) and it isn't blocked, you can return it to your hand as part of the ninjutsu cost of Mistblade Shinobi. If your opponent has a Smuggler's Copter that's a creature (perhaps they crewed it to block something) and your Mistblade Shinobi deals combat damage to them, you can return the copter to their hand with the triggered ability. If your opponent has a Smuggler's Copter that isn't a creature (maybe they have nothing to crew it with), you cannot return it to their hand with Mistblade Shinobi's triggered ability, because it can only target creatures.
August 3, 2018 4:27 p.m.
No, nothing special. If you attack with a crewed vehicle and it isn't blocked, then it's an unblocked attacking creature and can be used to pay that part of the cost of the Ninjutsu ability.