Answer by shea for Disable multisite-wide plugins on specific sites

Multisite-wide active plugins are stored in the active_sitewide_plugins site option. We can hook into this option and return an empty array (no plugins are active).

This snippet should be installed as a Must-Use Plugin.

<?php/** * Plugin Name: Disable Sitewide Plugins * Plugin URI: https://wordpress.stackexchange.com/q/107732/19726 * Author: Shea Bunge * Author URI: https://wordpress.stackexchange.com/users/19726/shea * Version: 0.1 */global $blog_id;if ( in_array( $blog_id, array( 6, 9, 42 ) ) {    add_filter( 'pre_site_option_active_sitewide_plugins', '__return_empty_array' );}

Remember to replace array( 6, 9, 42 ) with an array of the blog IDs you want to disable network-wide plugins on.