The Mellow-drive is a true e-skateboard for travel. It is small, compact and easy to bring with you - all you need is a deck when you arrive. Not only that, but it actually packs decent performance. The Mellow is also one of very few electric skateboards that has an assist feature, meaning that it will only aid you if you actually push.
The big downside to the Mellow is the price and (to some) the odd remote. I would also say that the initial setup process is a bit wonky.