Panache is style, someone who can carry off a different look effortlessly - I had a coworker who wore the most ridiculous clothes but looked good in them, I think that is panache. A fashion sense that is individual and loud and still looks good.
Charisma I think of as magnetic personality, the person who draws your attention, does not demand it. Usually people who do thrive on attention. Stage presence is a form of charisma, I went to see Marcus King and he is not good looking and had on a most unflattering outfit but as soon as he started playing I forgot all about that, he was absolutely stunning and attractive in the way he moved, sung, and played guitar. He had charisma.