The described functionality is not available out of the box in the ImageEditor, but you can customize its built-in InsertImage dialog in order to achieve it. For example, you can replace the insert URL option of the dialog with a predefined set of images, that will be inserted when the use click over them (you can use the logic of the click handler of the Set button in the InsertImage.ascx
Detailed information on how to customize the ImageEditor's dialogs is available here: Customize Built-in Dialogs
Hope this information will be helpful for you in order to implement the desired custom scenario.
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