So I'm looking at playing a Genesys fantasy setting that is using terrinoth as it's basis. I'm looking at taking a melee [heavy] signature weapon. I see that it has knockback. And in its description it talks about picking a weapon. If I go with a great site do I get the traits like defensive and the requirement to have 3 agility or are those just wiped away and replaced by the stat line under signature weapon.

By default the stats of the "weapon" you picked are wiped away and are just what it lists for the Melee [Heavy] signature weapon.

You could easily work with your GM to do something fancier for sure though.

I'm happy to remove the agility requirement and defensive properties and just have knock back.