couldnt kakashi just use his sharingan to copy how naruto ads his chakra nature to the rasengan since he is the copy ninja?even though he could only use it once
Kakashi doesn't have fire element, that's anime only, non-cannon.He may eventually do this, and combine lightning with rasengan, or may any other variety like fire and rasengan, water and rasengan....etc.
^That guy has it right.no that doesn't work. sharingan ables it's user to see how a technique gets done. and sharingan reads/sees and copies the hand seals.
it's copying ability cames from there. sharingan isn't copying a technique once someone uses in front of you. it just showes it's user how a technique is done. if user has the talent/skills he can use the technique.
kakashi sees through how the technique is done but he has neither the chakra nor the skills to do it. plus he cannot use wind.
therefore kakashi cannot copy rasenshuriken
Kakashi does not have the element of fire at his disposal.im not saying for wind style but for fire/lightning/water