WebScraper for Mac now has the option to download and save images in a folder, as well as, or instead of, extracting data from the pages.
WebScraper crawls a whole website and it can extract information based on a class or id, or dump the content as html, plain text or markdown.
By just checking that box and choosing a download location, it can also dump all images to a local folder. That includes those found linked (the target of a regular hyperlink), those in a <img src , and those found in an srcset.
If you only want particular images, you can select only those which match a partial url or regex.
This functionality is in version 4.1.0 which is available now.