The metadata in a photo received through WhatsApp can depend on how it was sent. An image sent as a photo may be resized or recompressed. Sending a file as a document is intended for file sharing, but behavior can vary by client, version, and workflow. Check the copy you receive instead of relying on a universal rule.
Compare the original and received copies
If the sender can share the original file, compare both versions with an EXIF viewer. Look at dimensions, file size, camera details, date, and GPS presence. A difference can show that the files were processed, but it does not describe every change to the pixels.
Keep private location fields in mind. If an original image contains GPS coordinates, consider whether the recipient needs that information before sending it as a file. The Motchilllz report indicates GPS presence without revealing exact coordinates.
Missing fields do not establish that an image was generated. Messaging apps, editors, screenshots, and exports can all change which metadata survives. For a broader explanation, see what photo metadata can reveal.