Swirling Shimmer

As a bonus action, the user of this weapon can
summon an exact copy of it into their free hand;
this copy perpetually shares the statistics and
conditions affecting the original.
Additionally, as a bonus action, any creature
wielding one of the weapons can teleport to an
unoccupied space within 5 feet of the other, if
it is further than 5 feet from them.
The user can banish the copy as a bonus action.