
wp-comment-validation can adds custom message for wordpress default comment submission form validation. It is easy to use , just install plugin and validation will be there on the comment submission form on whole site also can be set your own message to display on error just go to setting page of wp comment validation at left panel in wordpress.
Download & install the zip archive
The plugin package installer can be downloaded from the WP2E project tab called “code”.
1 – Select the version to download if this option is available otherwise the “latest” version of the main plugin will be used.
2 – After downloading the zip archive install the plugin package installer in you local environment and activate the script from the plugin list.
3 – Under the section “Plugins” of the admin dashboard you should see a new “Dependencies & Licenses” link. Follow the instructions from this panel to finalize the installation of the missing dependencies.
Tips: Use the WP2E panel to add/suggest new dependencies to the local installation. Press F5 in the list of dependencies if the changes are not displayed right away.