Is it possible to draw on the sprite image?

Is it possible to draw an outline of a sprite image from the Unity editor? I want to draw an outline like this in the example image.
What is the best way to do it?

  1. draw an outline on image using a paint tool, photoshop, or other editing software and draw it and bring it to Unity
  2. draw an outline on 2d sprite directly from Unity (if there is the tool)

I prefer 2 if there is Preformatted textalready a tool like that, but I could not find the solution.