This function will be available when selecting three or more images.
- To distribute the images evenly between the topmost and bottommost images, choose Vertically from the Distribute group in the Format tab in the right panel, or right-click the anchor image > Distribute > Vertically.
- To distribute the images evenly between the leftmost and rightmost images, choose Horizontally from the Distribute group in the Format tab, or right-click the anchor image > Distribute > Horizontally.
Below is an example:

