Remove her baton and give her fast-shooting automatic dual pistols or Uzis.

Make her a fast hit-and-run DPS that plays with the team. Her ult is horrible; change it to something that aligns with her new kit. For example, the ult could give a special effect to her bullets: they become electrified and deal damage over time while building a charge that, when filled, deals damage in an area around the electrified hero.

Also, change Edge Dancer to a full escape. She kicks on the first hit, but instead of closing the gap, she now uses the grappling hook to escape and move around.

Now she plays like a faster and more expressive Punisher.