Long hilted, like three times the length of a normal hilt, with the top third that can open up into something akin to a broadsword crossguard that has emitters to widen the blade, basically transforming it from a katana-esque weapon to a long/broadsword.
Not necessarily in the game, but in something of future Star Wars. Disney is known for their transforming swords in games (KH, for instance).
There are actually some like that already. Shoto is a short lightsaber, lightclub is a giant blade, lightwhip is a, well, whip, and dual-phase lightsabers switch between two preset lengths. Just a few examples. If you go to the SW Wikia and look up lightsabers, you can see a bunch of the variations.
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