Circle Hit Area

You can add a circular hit are to an object by seleting the CIRCLE shape in the Hit Area section. Then you can change the radius and position of the circle in the Hit Area (Circle) section:

Set the circle hit area.

Also, you can change the circle properties with the Edit Hit Area Tool (I):

Circle hit area tool.

The scene compiler generates code for setting the circle area in this way:

// wizball
const wizball = this.add.image(191, 161, "wizball");
wizball.setInteractive(
    new Phaser.Geom.Circle(46, 46, 46),
    Phaser.Geom.Circle.Contains);