Logic to run whatever activation scripts a WP plugin needs if activated network-wide.

WpNetworkActivation.php

<?php

function activation() {
    global $wpdb;
    
    // If we've got a multisite instance of WP
    if (function_exists('is_multisite') && is_multisite()) {
    
    // check if it is a network activation
        if (isset($_GET['networkwide']) && ($_GET['networkwide'] == 1)) {
            
            // Save our current blog
            $current_blog = $wpdb->blogid;
            
            // Get all blog ids
            $blogids = $wpdb->get_col($wpdb->prepare("SELECT blog_id FROM $wpdb->blogs"));
            
            // Loop through each blog ID, switch to it, and run whatever code our plugin needs during activation.
            foreach ($blogids as $blog_id) {
                // Switch to the next blog.
                switch_to_blog($blog_id);
                
                // Put your activation code here. This will run for each blog on the network.
            }
            
            // Switch back to the original blog.
            switch_to_blog($current_blog);
            return;
        }	
    } 
    // Put your activation code here. This will only run for a non-networked WP install.
}