Rename posts label to "Articles"

convert_post_label_to_article.php

<?php

// Alters post type labels.
add_action( 'registered_post_type', 'change_post_type_labels', 10, 2 );

// Posts menu label change to articles.
add_action( 'admin_menu', 'rename_post_menu_item_label' );

/**
 * Replace Posts label to Articles in post edit admin page
 *
 **/
function rename_post_menu_item_label() {
	global $menu;
	global $submenu;
	// 0 = menu_title, 1 = capability, 2 = menu_slug, 3 = page_title, 4 = classes
	foreach ( $menu as $key => $menu_item ) {
		// Subkey can be zero as well so $sub_key > -1 is used here.
		if ( in_array( 'Posts', $menu_item ) ) {
			if ( isset( $menu[ $key ] ) ) {
				$menu[ $key ][0] = 'Articles';
				$menu[ $key ][6] = 'dashicons-media-document';
			}
			if ( isset( $submenu['edit.php'][ $key ] ) ) {
				$submenu['edit.php'][ $key ][0] = 'All Articles';
			}
			break;
		}
	}
}

/**
 * Fires after a post type is registered .
 *
 * @since 3.3.0
 * @since 4.6.0 Converted the `$post_type` parameter to accept a WP_Post_Type object .
 *
 * @param string       $post_type        Post type .
 * @param WP_Post_Type $post_type_object Arguments used to register the post type .
 **/
public function change_post_type_labels( $post_type, $post_type_object ) {
	if ( 'post' !== $post_type ) {
		return;
	}
	$labels                     = $post_type_object->labels;
	$labels->name               = 'Articles';
	$labels->singular_name      = 'Article';
	$labels->add_new            = 'Add Article';
	$labels->add_new_item       = 'Add Article';
	$labels->edit_item          = 'Edit Article';
	$labels->new_item           = 'Article';
	$labels->view_item          = 'View Article';
	$labels->search_items       = 'Search Articles';
	$labels->not_found          = 'No Articles found';
	$labels->not_found_in_trash = 'No Articles found in Trash';
}