This is an example of a Carousel (Pro)
Very tedious to setup. You add the widget, then you have to embed as many image widgets as you have pictures, and manually add the image to each Image widget.
This is an example of an Image Carousel (Under General)
As you can see the image sizes are not consistent, though there may be a setting to set them all the same, or we may need to make sure the image sizes of each image match before uploading to the site.
This widget does easily let you browse and select one or more images at the same time
This is an example of a Slider. This lets you browse the Media Gallery to select a picture, but you have to add a placeholder for each picture in the Slider and then add an associated image to that placeholder. You cannot click on the image to open it up, but you could add the shortcode of the image to the button URL