I have a -5 energy hammer; pm me if interested in the stats.
I'm using it as a focus switching in PvP, works just as well as an axe or sword.
You don't need a shield since you will switch right back to regain energy.
as for people posting -5 energy hammers... read the post, says "axes and swords".... it's for taking away energy and he's using an offhand too, the more off the better, and... hammers take two hands. okay that's it