Board Thread:Support Requests - Community Management/@comment-9725237-20141009190106/@comment-4018164-20141014055842

MediaWiki's API allows you to do that with only JavaScript, so there's no need to download anything. It has a built-in image listing tool (which you can also use to list only certain images) and an upload tool, so you can theoretically get the URL of each image from a wiki X, and upload them to wiki Y.

Though a thing to remember when using the API- whenever submiting content to a wiki, you have to run your script in that wiki. So, for instance, if you wanted to import all images from the Community Central to the Spongebob wiki, you'd have to execute that script at the Spongebob wiki.