function themeslug_deactivate_stock_reports($from) {
 global $wpdb;
 return "FROM {$wpdb->posts} as posts WHERE 1=0";
}
add_filter( 'woocommerce_report_low_in_stock_query_from', 'themeslug_deactivate_stock_reports' );
add_filter( 'woocommerce_report_out_of_stock_query_from', 'themeslug_deactivate_stock_reports' );