Its f7 that u need to use to get BLANK KEY FRAMES.
f6 is for inserting keyframe- to make the same thing come over again
use f7 , click the onion skin button as shown, make another layer for sword .
for the sword, make it as a symbol.click f6 to make it continue towards ur key frames.move it to desired position matching ur stickfigure.
hope that helped :)