Board Thread:Theories and Speculation/@comment-32742265-20180119154238/@comment-734582-20180126062131

Omnibender wrote: Prove that Kakashi has access to all five specifically because of the Sharingan. To add to this, even Sasuke had to train in Lightning Release. Yet he performed Fireball with knowing apparently only the seals, pre-sharingan. Clearly the sharingan doesn't make you equally capable at every nature transform. It's still a tool, one that needs skill to be wielded. And while it makes a lot of skill requirements softer (e.g it makes jutsu easier to understand and learn), it doesn't make them all equivalent.

Kakashi clearly favored Lightning Release followed by Earth and Water. Sasuke clearly favored Lightning and Fire. I think it's clear that the user's skill still counts.