Energy Swords are a hi-tech form of weapon used by the Knights of Mata-Nui. The Energy Sword is a compact weapon, extremely quick. Though it does not usually cause as much damage as heavier weapons. Most members use them in pairs of two.
It works by projecting a solid beam of light through a rare form of Protodermis, only available on Metru-Nui and even then only in small reserves.
Each Energy Sword is directly taylored to the unique elemental signatue. In other words, Sirea couldn't say, use Kanai's Energy Swords.
Energy Staves are similar to the Energy Swords, except they are spears with an energy blade on the end of them. They can be modified to have a blade on either end, though usually they only have one blade.
As with Energy Swords, the Energy Staff is uniquely taylored to the users elemental signature. No one else but that person could use that specific staff.