In the original promotional picture for the Halloween event if you look closely at the samurai you can make out the shape of a swords hilt on the right:
(If you have a better quality image of this promotional picture please share)
A little closer:
Perhaps there could be a variant of this skin, with a katana on his belt.
@ShrimpTofu made a great suggestion on the original operation earth shield news post, showing what this could look like:
