Like I've maintained long ago, Raggens :P

Be glad she's available in World of Light, by which you can decrease the difficulty and spam your Staff item.

This fight, on the other hand, was a pure nightmare. You would have to sell your soul to the Devil just to beat that spirit battle. I lucked out a few times and won the battle, but it's impossible on other occasions.
Really wish the development team would significantly nerf this asshole to oblivion.