<?php
add_action( 'added_post_meta', 'mp_sync_on_product_save', 10, 4 );
add_action( 'updated_post_meta', 'mp_sync_on_product_save', 10, 4 );
function mp_sync_on_product_save( $meta_id, $post_id, $meta_key, $meta_value ) {
    if ( $meta_key == '_edit_lock' ) { // we've been editing the post
        if ( get_post_type( $post_id ) == 'product' ) { // we've been editing a product
            $product = wc_get_product( $post_id );
            // do something with this product
        }
    }
}
?>