Meteor hammer feels like it ought to be able to be used to block melee attacks since the rope/chain can still be used to get in the way of things, let alone knocking things off trajectory with the tip. If limitations needs to be put on it, I'd rather suggest it asking to attack with agility only.
Actually ctrl+f reveals no block mechanic implemented, Guard requires the guard tag, unless blocking here is intended to be an umbrella term to catch Parry, Counter, Guard and Bind?