Google’s John Mueller said on Twitter that it is fine for multilingual sites to use the same image and image source URLs for translated pages but the alt attributes for those images should be localized and translated into the local language.
That should make sense, I mean, if you have a picture of a sun and the alt-attribute says “picture of sun” and then you use that same photo on a French translated page, maybe the alt attribute should be translated to French?
Here are the tweets:
Using the same image URL is fine, but the alt-attribute should be localized on the localized pages.
— 🍌 John 🍌 (@JohnMu) March 5, 2019
Forum discussion at Twitter.