I think that what you may need is a tool (internal / plugin) that supports regular expression search queries. For example, within the Markdown editor (the latest, not legacy), you may use the search & replace dialog to search for images pointing at URLs like this: (or an enhanced variation on this !\[\w*\]\(http regex)
The drawback is that you have to go note by note and search for these images.
I'm not sure that we currently have a plugin that enables regex search throughout all notes, maybe the VS Code Style Search plugin. If you have no other available option, you could tweak the Inline Tag Navigator to find all such images for you, as a workaround (let me know if you need guidance).