The idea of a sword in ODST was one of the original easter eggs that people searched for. It is now generally agreed that it does not exist.
The images show the Sword Spree where the Hammer Spree normally is, with no extra space for the Hammer Spree. I am guessing these images are faked and photoshopped.
EDIT: Apparently there is not so much agreement, but that is my personal opinion.