We've improved Image Block with new pre-made styles to make speed up your design workflow and Unleash your creativity to create your dream website. By default WordPress 5.9 comes with two styles Default square and Rounded shapes.
Navigate to Image Block Settings > Style and pick the style that matches your need.
- Mask Flower: Add your image in Flower shape.
- Mask Sketch: Add your image in Sketch shape.
- Mask Blob: Add your image in Blob shape.
- Shadow: Round your image with shadow.