module-admin-order-columns/Plugin/Order/View/Items/Renderer/DefaultRenderer.php

<?php
namespace Shopkeeper\AdminOrderColumns\Plugin\Order\View\Items\Renderer;

use Magento\Catalog\Api\ProductRepositoryInterface;
use Magento\Framework\Exception\NoSuchEntityException;

class DefaultRenderer
{
    protected $productRepository;

    public function __construct(
        ProductRepositoryInterface $productRepository
    ) {
        $this->productRepository = $productRepository;
    }

    /**
     * Modify columns to remove tax columns and add cost column
     *
     * @param \Magento\Sales\Block\Adminhtml\Order\View\Items\Renderer\DefaultRenderer $subject
     * @param array $result
     * @return array
     */
    public function afterGetColumns($subject, $result)
    {
        // Remove tax columns
        unset($result['tax-amount']);
        unset($result['tax-percent']);

        // Add cost column after price
        $newColumns = [];
        foreach ($result as $key => $value) {
            $newColumns[$key] = $value;
            if ($key === 'price') {
                $newColumns['cost'] = 'col-cost';
            }
        }

        return $newColumns;
    }

    /**
     * Add HTML rendering for cost column
     *
     * @param \Magento\Sales\Block\Adminhtml\Order\View\Items\Renderer\DefaultRenderer $subject
     * @param string $result
     * @param \Magento\Sales\Model\Order\Item $item
     * @param string $column
     * @return string
     */
    public function afterGetColumnHtml($subject, $result, $item, $column)
    {
        if ($column === 'cost') {
            try {
                $product = $this->productRepository->getById($item->getProductId());
                $cost = $product->getCost();
                if ($cost) {
                    return $subject->getOrder()->formatPrice($cost);
                } else {
                    return __('N/A');
                }
            } catch (NoSuchEntityException $e) {
                return __('N/A');
            }
        }

        // Make product name and SKU clickable
        if ($column === 'product') {
            $productUrl = $subject->getUrl('catalog/product/edit', ['id' => $item->getProductId()]);
            
            // Replace product name with linked version
            $productName = $item->getName();
            $linkedName = '<a href="' . $productUrl . '" target="_blank" title="' . __('Edit Product') . '">' 
                        . $subject->escapeHtml($productName) . '</a>';
            $result = str_replace($subject->escapeHtml($productName), $linkedName, $result);
            
            // Replace SKU with linked version  
            $sku = $item->getSku();
            $linkedSku = '<a href="' . $productUrl . '" target="_blank" title="' . __('Edit Product') . '">' 
                       . $subject->escapeHtml($sku) . '</a>';
            $result = str_replace($subject->escapeHtml($sku), $linkedSku, $result);
        }

        return $result;
    }

    /**
     * Add column header for cost
     *
     * @param \Magento\Sales\Block\Adminhtml\Order\View\Items\Renderer\DefaultRenderer $subject
     * @param string $result
     * @param string $columnName
     * @return string
     */
    public function afterGetHeaderText($subject, $result, $columnName)
    {
        if ($columnName === 'cost') {
            return __('Cost');
        }
        return $result;
    }
}