How to Download Older Versions of WordPress Plugins

First, go to the WordPress.org site and navigate to the Plugins tab. Here search for the WordPress plugin you want to downgrade.

After searching for your plugin, click on the “Advanced View” link on the right.

Scroll down your page and click on "Development Version" then select the version of the plugin from the drop down menu and download it for your WordPress site.

When you select the plugin version and click on the "Download" link, your plugin will start downloading.

You can install and activate it by going to the WordPress dashboard or you can install it using FTP.