Runtime Source URL property access of an Image widget

Josue, widget properties are generally locked down to the Mashup builder stage. You can't access them through services. What you can do is build services around them, and feed in those properties through your service output.

For example, the Image widget's SourceURL property requires a form of text input to select the right media entity, so you can bind a service that outputs text to it. Or you can bind a text box to the same property and type in the name of your existing media entity or maybe list the entire selection of media entities on a List widget and bind the selected rows here, so any time you select a row, the image would change.