Board Thread:Episode Discussions/@comment-1181222-20160728115522/@comment-25122992-20160728204120

I don't think the issue is in the lens which wasn't removed. The lenses turned Kakashi's eyes grey when he was disguised as Sukea. In Kakashi's pic of both omake and anime adaptation, both his eyes are coloured typically black. So it's rather an error, because if the lens remained in Kakashi's left eye, it'd still be grey and thus differ from the right eye in colouring.