Use PHP and the WordPress API. Place the following in copy-options.php
and FTP it to wp-content/plugins
, then activate it from the main site:
<?php
/**
* Plugin Name: Copy Options
* Plugin URI: http://wordpress.stackexchange.com/q/186092/1685
* Description: Copy options from site 2 to site 1.
* Version: 0.1
* Author: TheDeadMedic
* Author URI: http://wordpress.stackexchange.com/users/1685/thedeadmedic
*/
function wpse_186092_copy_options() {
if ( 2 !== $blog_id = get_current_blog_id() )
switch_to_blog( 2 );
// Get all options from blog 2
$options = wp_load_alloptions();
// Switch to main blog
switch_to_blog( 1 );
foreach ( $options as $name => $value )
update_option( $name, $value ); // Will update option if exists, insert if not
// Switch back to current blog
switch_to_blog( $blog_id );
}
register_activation_hook( __file__, 'wpse_186092_copy_options' );
Backup first. This code is not tested and comes without warranty.