One of the pieces you can upgrade on your lightsaber is the Emitter. Check out this Star Wars Jedi Fallen Order lightsaber emitter location guide to find them all. With these you can make your lightsaber look like other Jedi sabers from the universe.
Star Wars Fallen Order Lightsaber Emitter Location Guide
Climb up the small building there and at the top you will find the emitter in the chest.