post-order-by-category.php

<?php
/*
Plugin Name: Change post order by category
Plugin URI: https://www.damiencarbery.com
Description: Order Blog category by date, rest alphabetically.
Author: Damien Carbery
Version: 0.1
*/


// Change the post order to ascending by title for all categories except the 'blog' category.
add_action( 'pre_get_posts', 'dcwd_change_post_order_by_category' );
function dcwd_change_post_order_by_category( $query ) {
	if ( ! is_admin() && $query->is_main_query() ) {
		if ( ! is_category( 'blog' ) ) {
			$query->set( 'orderby', 'title' );
			$query->set( 'order', 'asc' );
		}
	}
}