Alex Moss

Google+ comments was introduced in April 2013 to blogger.com users. This plugin lets you add Google+ comments to your WordPress site!
Simply install the plugin and follow the instructions on the Settings page.
<ul>
<li><a href="http://3doordigital.com/wordpress/plugins/google-plus-comments/" rel="nofollow ugc">Google+ Comments</a> Plugin homepage.</li>
<li>More <a href="http://3doordigital.com/wordpress/plugins/" rel="nofollow ugc">WordPress Plugins</a>.</li>
</ul>
You can also insert the comment box as a shortcode into any post, page or template and use your own settings for each time you do it! Simply use the shortcode [gp-comments]

Google+ Comments

The Google+ Comments WordPress plugin makes it easier for you to setup, administer and customise Google+ comments from your WordPress site.

Scott Reilly

This plugin enables a user with the administrator role the ability to comment on any post or page, even if the comments for that post or page are closed. When the plugin is active, this behavior is automatically enabled.
Administrators can be explicitly prevented from commenting on specific posts via two approaches:
<ul>
<li>When creating or editing a post, in the “Prevent Admin Comments” metabox (in the block editor) or the “Discussion” metabox (in the classic editor) there is a checkbox labeled “Prevent administrators from commenting” that only administrators can access. Checking the checkbox will prevent administrators from commenting on the post even though this plugin is active. (If the metabox isn’t visible for you when using the classic editor, then expand the “Screen Options” slide-down panel on the upper-right of the page.)</li>
<li>Programmatically, via the use of the ‘c2c_admin_can_always_comment_disable’ filter. This can be used be provide more fine-grained access control and contextual handling. See the “Hooks” section for documentation on the filter’s use.</li>
</ul>
Links: <a href="https://coffee2code.com/wp-plugins/always-allow-admin-comments/" rel="nofollow ugc">Plugin Homepage</a> | <a href="https://wordpress.org/plugins/always-allow-admin-comments/" rel="ugc">Plugin Directory Page</a> | <a href="https://github.com/coffee2code/always-allow-admin-comments/" rel="nofollow ugc">GitHub</a> | <a href="https://coffee2code.com" rel="nofollow ugc">Author Homepage</a>
<h3>Developer Documentation</h3>
Developer documentation can be found in <a href="https://github.com/coffee2code/always-allow-admin-comments/blob/master/DEVELOPER-DOCS.md" rel="nofollow ugc">DEVELOPER-DOCS.md</a>. That documentation covers the hooks provided by the plugin.
As an overview, these are the hooks provided by the plugin:
<ul>
<li><code>c2c_always_allow_admin_comments_disable</code> : Customizes if comments should actually be disabled for a particular admin user.</li>
<li><code>c2c_always_allow_admin_comments_post_types</code>: Customizes which post types are supported by the plugin.</li>
</ul>

Always Allow Admin Comments

Allow an admin user (when logged in) to always be able to comment on a post, even if comments are closed for the post.

Google+ Comments vs Always Allow Admin Comments