I’ve been using the following code to display custom columns in the Woocommerce admin orders page:

// Add Order notes Column to Admin Orders Page
add_filter( 'manage_woocommerce_page_wc-orders_columns', 'woocommerce_add_order_notes_column' );

function woocommerce_add_order_notes_column( $columns ) {
    return array_slice( $columns, 0, 8, true )
    + array( 'order_notes' => __( 'Order Notes', 'woocommerce' ) )
    + array_slice( $columns, 8, NULL, true );

    return $ordered_columns;
}

// Get Order notes
add_action( 'manage_woocommerce_page_wc-orders_custom_column' , 'woocommerce_show_order_notes_column', 10, 2 );

function woocommerce_show_order_notes_column( $column_name, $order_id ) {
    switch ( $column_name ) {
        case 'order_notes':
            $order = wc_get_order( $order_id );
            $note = $order->get_customer_note();
            if ( !empty($note) ) {
                echo '<span class="note-on tips" data-tip="' . wc_sanitize_tooltip( $note ) . '">' . __( 'Yes', 'woocommerce' ) . '</span>';
            } else {
                echo '<span class="na">–</span>';
            }
            break;
    }
}


// Add 'Pre-order Products' Column to Admin Orders Page
add_filter( 'manage_woocommerce_page_wc-orders_columns', 'woocommerce_add_preorder_products_tick_column' );

function woocommerce_add_preorder_products_tick_column( $columns ) {
    $ordered_columns = array();
    
    foreach( $columns as $key => $column ){
        $ordered_columns[$key] = $column;
        if( 'wc_actions' == $key ){
            $ordered_columns['preorder_products_tick'] = __( 'Pre-orders', 'woocommerce');
        }
    }

    return $ordered_columns;
}

// Get Pre-order Products
add_action( 'manage_woocommerce_page_wc-orders_custom_column' , 'add_items_to_preorder_products_tick_column' );

function add_items_to_preorder_products_tick_column( $colname ) {
    global $the_order;

    if( $colname == 'preorder_products_tick' ) {

        // get items from the order global object
        $order_items = $the_order->get_items();

        if ( !is_wp_error( $order_items ) ) {
            foreach( $order_items as $order_item ) {
            $product_id = $order_item->get_product_id();  
                if ( has_term( array( 'comic-book-pre-orders', 'dc-comics-pre-orders', 'image-comics-pre-orders', 'marvel-comics-pre-orders', 'other-publisher-pre-orders' ), 'product_cat', $product_id ) ) {
                    echo "✔";
                }
            }   
        }
    }
}


// Add 'Total Sales' column to the products list
// add column
add_filter( 'manage_edit-product_columns', 'column_total_sales_1', 20 );
// populate column
add_action( 'manage_posts_custom_column', 'column_total_sales_2' );
// make column sortable
add_filter('manage_edit-product_sortable_columns', 'column_total_sales_3');
// how to sort column
add_action( 'pre_get_posts', 'column_total_sales_4' );

function column_total_sales_1( $columns_array ) {
    return array_slice( $columns_array, 0, 8, true )
    + array( 'total_sales' => 'Total Sales' )
    + array_slice( $columns_array, 8, NULL, true );
}

function column_total_sales_2( $column_id ) {
    if( $column_id  == 'total_sales' )
        echo get_post_meta( get_the_ID(), 'total_sales', true );
}

function column_total_sales_3( $a ){
    return wp_parse_args( array( 'total_sales' => 'by_total_sales' ), $a );
}

function column_total_sales_4( $query ) {
    if( !is_admin() || empty( $_GET['orderby']) || empty( $_GET['order'] ) )
        return;
    if( $_GET['orderby'] == 'by_total_sales' ) {
        $query->set('meta_key', 'total_sales' );
        $query->set('orderby', 'meta_value_num');
        $query->set('order', $_GET['order'] );
    }
    return $query;
}

// Make stock column sortable
add_filter( 'manage_edit-product_sortable_columns', 'wcss_make_stock_sortable' );
function wcss_make_stock_sortable( $sortable_columns ) {

   $sortable_columns[ 'is_in_stock' ] = '_stock';
   return $sortable_columns;
}

I’m now in the process of updating to High-Performance Order Storage (HPOS) and this code no longer works.

Can anyone advise me how I can update the code to work with HPOS please, as I’m completely lost!

Any advise would be very much appreciated, thank you!