No. While you can download an application's folder from the server, plugins aren't the same. When plugins are installed, the setup folder is NOT saved on the server. And the original XML file is not available, either.
You'll need to rebuild the XML file from scratch based on the files on the server, plus rewrite from scratch the setup folder (if the plugin creates tables or adds columns).
It may take some time, but it can be done. I've done it several times for clients, especially recently after the marketplace closed.