Add your Text as a "Text Template" - https://docs.pteavstudio.com/en-us/11.0/how_to_v11/add_text#insert_text_template
Position and Size it by dragging to the bottom right in Objects and Animation. Size by using the Zoom control in Animation Tab or use grab handles. Save as a Style and Apply it to Single or Multiple Images/Slides.
Try this Style - drag an image into the Slide List (it will assume Main Object/Index 1 - see O&A Properties Tab) and Import and Apply this Style.
Text Template - Date.ptestyle
Import a Style: https://docs.pteavstudio.com/en-us/11.0/slide-styles/import
Apply a Style: https://docs.pteavstudio.com/en-us/11.0/slide-styles/apply
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