对于可变产品，当袜子数量超过**50时，以下将限制袜子数量显示为50**：

add_action( 'woocommerce_after_shop_loop_item', 'wc_loop_get_product_stock_availability_text', 10 );
function wc_loop_get_product_stock_availability_text() {
    global $wpdb, $product;

    $max_stock_qty = 50; // Maximum Number of Available Stock qty

    // For variable products
    if( $product->is_type('variable') ) {

        // Get the stock quantity sum of all product variations (children)
        $stock_quantity = $wpdb->get_var("
            SELECT SUM(pm.meta_value) FROM {$wpdb->prefix}posts as p
            JOIN {$wpdb->prefix}postmeta as pm ON p.ID = pm.post_id
            WHERE p.post_type = 'product_variation'
            AND p.post_status = 'publish' AND p.post_parent = '".get_the_id()."'
            AND pm.meta_key = '_stock' AND pm.meta_value IS NOT NULL
        ");

        if ( $stock_quantity > 0 ) {
            // Here we limit the sock quantity display to 50 when it's up to 50
            $stock_quantity = $stock_quantity >= $max_stock_qty ? $max_stock_qty : $stock_quantity;
            
            echo '<p class="stock in-stock">'. sprintf( __("%s in stock", "woocommerce"), $stock_quantity ).'</p>';
        } else {
            if ( is_numeric($stock_quantity) )
                echo '<p class="stock out-of-stock">' . __("Out of stock", "woocommerce") . '</p>';
            else
                return;
        }
    }
    // Other products types
    else {
        echo wc_get_stock_html( $product );
    }
}

字符串
代码放在你的活动子主题（或活动主题）的functions.php文件中。它应该可以工作。
相关：在Woocommerce存档页面中显示所有产品类型的库存可用性