Bright suns, Stéphanie! Welcome to planDisney.
So you're traveling to
Batuu and thinking about building your own droid at
Droid Depot or lightsaber at
Savi's Workshop? Impressive. Most impressive. Once you complete your mission, you must then embark on a journey beyond the stars, back to Earth. And you wonder—will these treasures of the Resistance (or the First Order, if that is your path) make it past the sentinels of off-world security? Fear not, for I have gathered the knowledge you seek.
The off-world enforcers, known as TSA, permit both lightsabers and droids to pass through their security gates. A lightsaber, though powerful, is allowed in both carry-on and checked cargo. Many travelers prefer to keep their lightsaber close, for who would trust such a relic in the belly of a starship? Overhead compartments or the care of a flight attendant will often be your best allies.
As for your astromech companion, it, too, may journey in either your carry-on or your checked cargo. But be warned—droids contain electronic components, and the sentinels may request additional inspection. A mere formality, but one to be mindful of. Should your unit be powered by lithium cells, certain starships (or, as you call them, airlines) require them to remain in carry-on storage rather than the underbelly of the craft.
Beyond the stars, in lands unknown, customs officers may have their own rules regarding these artifacts. Most will grant passage without question, yet a wise traveler always consults the customs agency of their destination before making the jump to hyperspace.
Prepare well, secure your cargo, and may the stars guide you safely to your next adventure. And remember—may the Force (and your souvenirs) be with you, always.
Mike