@andrejz actually you can use Python and OpenPyxl and KNIME to extract the images and save them in a subfolder as PNG files:
You will have to see if it does work with all images.
To have the results in an organised way they are in a sub-folder and carry the file name, the sheet and their cell the name. A list is also being provided.
In the subfolder there is a Jupyter notebook (kn_example_python_excel_image_extract.ipynb) to play around with the code and settings
kn_example_python_excel_image_extract.knwf (761.1 KB)