Need to add SKU to order confirmation email - Commerce 2
I found this article that helped:

https://www.drupal.org/forum/support/module-development-and-code-questions/2018-08-23/drupal-8-commerce-2-get-item-from

This is my commerce-order-receipt twig that displays the quantity, title, price and in a row below the sku.

Hope it helps.

 &lt;table style="text-align: center; width: 100%; margin: 5px auto 0 auto; border: 1px solid #cccccc; border-radius: 5px; padding: 40px 30px 30px 30px;"&gt;
    &lt;tbody&gt;
    &lt;tr&gt;
      &lt;td style="font-size: 30px; padding-bottom: 30px"&gt;{{ 'Order Confirmation'|t }}&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td style="font-weight: bold; padding-top:15px; padding-bottom: 15px; text-align: left; border-top: 1px solid #cccccc; border-bottom: 1px solid #cccccc; vertical-align: top;"&gt;
        {{ 'Order #@number details:'|t({'@number': order_entity.getOrderNumber}) }}
      &lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td style="vertical-align: top;"&gt;
        {% block order_items %}
        &lt;table style="padding-top: 15px; padding-bottom:15px; width: 100%"&gt;
          &lt;tbody style="text-align: left;"&gt;
          {% for order_item in order_entity.getItems %}
           {% set product = order_item.getPurchasedEntity %}
          &lt;tr&gt;
            &lt;td style="vertical-align: top;"&gt;
              {{ order_item.getQuantity|number_format }} x
            &lt;/td&gt;
            &lt;td style="vertical-align: top;"&gt;
              &lt;span&gt;{{ order_item.label }}&lt;/span&gt;
              &lt;span style="float: right;"&gt;{{ order_item.getTotalPrice|commerce_price_format }}&lt;/span&gt;
            &lt;/td&gt;
          &lt;/tr&gt;
          &lt;tr&gt;
          &lt;td style="vertical-align: top;"&gt;
              &lt;span&gt;SKU:&lt;/span&gt;
          &lt;/td&gt;
          &lt;td style="vertical-align: top;"&gt;
              &lt;span&gt;{{ product.getSku }}&lt;/span&gt;              
          &lt;/td&gt;
          &lt;/tr&gt;
          {% endfor %}
          &lt;/tbody&gt;
        &lt;/table&gt;
        {% endblock %}
      &lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td&gt;
        {% if (billing_information or shipping_information) %}
        &lt;table style="width: 100%; padding-top:15px; padding-bottom: 15px; text-align: left; border-top: 1px solid #cccccc; border-bottom: 1px solid #cccccc"&gt;
          &lt;tbody&gt;
          &lt;tr&gt;
            {% if shipping_information %}
              &lt;td style="padding-top: 5px; font-weight: bold; vertical-align: top;"&gt;{{ 'Shipping Information'|t }}&lt;/td&gt;
            {% endif %}
            {% if billing_information %}
              &lt;td style="padding-top: 5px; font-weight: bold; vertical-align: top;"&gt;{{ 'Billing Information'|t }}&lt;/td&gt;
            {% endif %}
          &lt;/tr&gt;
          &lt;tr&gt;
            {% if shipping_information %}
              &lt;td style="vertical-align: top;"&gt;
                {% block shipping_information %}
                  {{ shipping_information }}
                {% endblock %}
              &lt;/td&gt;
            {% endif %}
            {% if billing_information %}
              &lt;td style="vertical-align: top;"&gt;
                {% block billing_information %}
                  {{ billing_information }}
                {% endblock %}
              &lt;/td&gt;
            {% endif %}
          &lt;/tr&gt;
          {% if payment_method %}
            &lt;tr&gt;
              &lt;td style="font-weight: bold; padding-top: 40px; vertical-align: top;"&gt;{{ 'Payment Method'|t }}&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr&gt;
              &lt;td style="vertical-align: top;"&gt;
                {% block payment_method %}
                  &lt;p&gt;{{ payment_method }}&lt;/p&gt;
                {% endblock %}
              &lt;/td&gt;
            &lt;/tr&gt;
          {% endif %}
          &lt;/tbody&gt;
        &lt;/table&gt;
        {% endif %}
      &lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td style="padding-top: 20px; text-align: right;"&gt;
        {{ 'Subtotal: @subtotal'|t({'@subtotal': totals.subtotal|commerce_price_format}) }}
      &lt;/td&gt;
    &lt;/tr&gt;
    {% for adjustment in totals.adjustments %}
    &lt;tr&gt;
      &lt;td style="text-align: right;"&gt;
        {{ adjustment.label }}: {{ adjustment.total|commerce_price_format }}
      &lt;/td&gt;
    &lt;/tr&gt;
    {% endfor %}
    &lt;tr&gt;
      &lt;td style="padding-top: 10px; padding-bottom: 20px; font-size: 24px; text-align: right;"&gt;
        {{ 'Order Total: @total'|t({'@total': order_entity.getTotalPrice|commerce_price_format}) }}
      &lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
      &lt;td style="padding-top: 30px; border-top: 1px solid #cccccc;"&gt;
        {% block additional_information %}
          {{ 'Thank you for your order!'|t }}
        {% endblock %}
      &lt;/td&gt;
    &lt;/tr&gt;
    &lt;/tbody&gt;
  &lt;/table&gt;