There was a download of Dropbox Export Plug-in for Adobe Lightroom 2.7.1 on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. We recommend checking the downloaded files with any free antivirus. This software was originally produced by AlloyPhoto. The program lies within System Utilities, more precisely Plugins Addons. The most popular versions among the software users are 2.7, 1.9 and 1.6.
From the developer:
Dropbox Export Plug-in for Adobe Lightroom allows you to export photos from Adobe Lightroom directly to your Dropbox account. The program can import existing folder structure from Dropbox into your Lightroom catalog. It provides automatic pairing of online photos with photos in your catalog.
You may want to check out more software, such as Adobe Lightroom Classic CC, Adobe Lightroom CC or Piwigo Export Plug-in for Adobe Lightroom, which might be related to Dropbox Export Plug-in for Adobe Lightroom.