要在Woocommerce中实现最高统一运费和当地自取的功能，您可以使用以下代码示例：

1. 首先，在functions.php文件中添加以下代码来创建一个新的运费方式“Local Pickup Plus”：

function add_local_pickup_plus_shipping_method( $methods ) {
    $methods['local_pickup_plus'] = 'Local Pickup Plus';
    return $methods;
}
add_filter( 'woocommerce_shipping_methods', 'add_local_pickup_plus_shipping_method' );

class WC_Local_Pickup_Plus extends WC_Shipping_Method {

    public function __construct() {
        $this->id                 = 'local_pickup_plus';
        $this->method_title       = __( 'Local Pickup Plus', 'woocommerce' );
        $this->method_description = __( 'Local pickup plus shipping method', 'woocommerce' );

        $this->supports = array(
            'shipping-zones',
            'instance-settings',
            'instance-settings-modal',
        );

        $this->init();
    }

    public function init() {
        $this->instance_form_fields = array(
            'title' => array(
                'title'       => __( 'Title', 'woocommerce' ),
                'type'        => 'text',
                'description' => __( 'This controls the title which the user sees during checkout.', 'woocommerce' ),
                'default'     => __( 'Local Pickup Plus', 'woocommerce' ),
                'desc_tip'    => true,
            ),
            'cost' => array(
                'title'       => __( 'Cost', 'woocommerce' ),
                'type'        => 'text',
                'placeholder' => '',
                'description' => __( 'Enter a cost (e.g. 10.00) or a percentage value (e.g. 5%).', 'woocommerce' ),
                'default'     => '',
                'desc_tip'    => true,
            ),
        );

        add_action( 'woocommerce_update_options_shipping_' . $this->id, array( $this, 'process_admin_options' ) );
    }

    public function calculate_shipping( $package = array() ) {
        $this->add_rate(
            array(
                'id'    => $this->id,
                'label' => $this->title,
                'cost'  => $this->get_option( 'cost' ),
            )
        );
    }
}

2. 然后，在functions.php文件中添加以下代码来设置最高统一运费：

function custom_wc_flat_rate_shipping_method_1( $rates, $package ) {
    $max_shipping_cost = 10; // 设置最高运费

    foreach ( $rates as $rate_id => $rate ) {
        if ( 'flat_rate:1' === $rate_id && $rate->cost > $max_shipping_cost ) {
            $rates[ $rate_id ]->cost = $max_shipping_cost;
        }
    }

    return $rates;
}
add_filter( 'woocommerce_package_rates', 'custom_wc_flat_rate_shipping_method_1', 10, 2 );

3. 最后，您需要在Woocommerce后台设置中启用“Local Pickup Plus”运费方式，并设置相关选项。

通过以上步骤，您将能够实现Woocommerce中的最高统一运费和当地自取功能。请根据您的实际需求调整代码中的配置和选项。