Is this method worse than WordPress web-interface uploads?

1. You should always use the WordPress media uploader unless there’s something preventing you from doing so.
2. The plugin will COPY the file, but only if the file exists outside of the uploads directory. If you import a file from /wordpress/wp-content/uploads/my-folder/ it will NOT copy it, but if you import from /wordpress/wp-content/my-files/ it WILL.
3. The permissions or visibility are unchanged AFAIK, this may vary on your server configuration though.
4. If you attempt to import something that’s already in the media library, it should do nothing. No guarantee’s though since the plugin was written so long ago, and mostly now unmaintained.

Thanks. The file is placed in wp-content/upload section, so I think there’s no problem in using this plugin.

Well, it does do something for me importing a file that’s already in the uploads folder, it solves the problem of files not showing up in the Media Library.

The issue is that importing using the file dates doesn’t work with WP, however the files have been physically copied from server location to the WP uploads folder.

You need to set the import date to the current time as file time is checked by default.

If you have already imported files using the file time then going to the uploads folder and re-selecting the files and re-importing them with the current time selected will make the images now appear in Media Library.