Actually in the Force Unleashed wookies with Ryyk blades were able to block Vader's light saber by crossing both blades. so Ryyk blades are onebut their must be two.
You're forgetting the principles of KISS. Either all weapons will be able to block lightsabers (as in the KOTOR games, where they're assumed to have a basic cortosis weave) or none of them will be.
I expect that it will likely be assumed that all weapons will have trace elements of cortosis, and be able to block lightsabers. But that's just my guess.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Lightsabers work like any other weapon, just like in most MMOs, console games, etc. They have a damage factor per hit and follow combat rules like other weapons. There's no such thing as them automatically slicing someone in half or whatever you're imagining for some reason.
Cortosis, phrik, beskar, ultrachrome, neutronium, darkswords, Bane's parasites the name of which I can't remember right now, any objects imbued with Force Weapon, any objects created or altered by Sith Alchemy, probably some more stuff I can't remember.
This list is from memory, it's been a while since I've been on Wookieepedia. Regardless though, the rarity of the materials combined with the nature of damage in a game means that most likely all weapons will have a measure of resistance against a lightsaber.