Here we go xD the left and right hand lightning xD
Make separate segments with only the origins changed. Like this:
origin 0 -10 -1 0 -7 1
origin 0 10 1 0 7 1
Change the origin values depending on how far apart the hands are.
Note that because of this spawnflag, both bolts will end on the same location. If you don't want that, you need to set a origin2.