Sean Hayes

Comments On is a plugin that adds a column to the “All Posts” or “All Pages” view in the Admin dashboard. The column will display one of three options for the related post/page: “open”, “closed” or “registered_only”.
Now, quickly and easily, without having to click “Quick Edit” or “Edit” for each post you can find out which posts/pages can accept comments and which can’t.
It is an ideal companion for the Comment count column alerting you to content that hasn’t any comments. Or it can highlight any posts/pages that might not be enabled for comments.

Comments On

Comments On adds a column to the "All Posts"/"All Pages" view in the Admin dashboard showing the status of comments.

tyfdesign

When activated, this plugin: 
1. Closes comments and pings on all existing public content (posts, pages, and custom post types). 
2. Sets WordPress defaults to disallow new comments and pings on all future content. 
3. Ensures that newly created or updated posts remain closed to comments. 
4. Hides the default Comments menu in the admin sidebar when enabled. 
5. Provides a simple Settings page with a single Activate / Deactivate button to toggle behavior.
When deactivated, the plugin restores the default WordPress discussion settings without reopening previously closed comments.
Created by TYF Design.

Do Not Allow Comments Everywhere

A lightweight plugin that globally disables comments and pings across all WordPress content - past and future.

Comments On vs Do Not Allow Comments Everywhere