You need to override this file
/vendor/magento/module-checkout/CustomerData/DefaultItem.php
and add call sort description value here like below
/**
* {@inheritdoc}
*/
protected function doGetItemData()
{
$imageHelper = $this->imageHelper->init($this->getProductForThumbnail(), 'mini_cart_product_thumbnail');
$productName = $this->escaper->escapeHtml($this->item->getProduct()->getName());
return [
'options' => $this->getOptionList(),
'qty' => $this->item->getQty() * 1,
'item_id' => $this->item->getId(),
'configure_url' => $this->getConfigureUrl(),
'is_visible_in_site_visibility' => $this->item->getProduct()->isVisibleInSiteVisibility(),
'product_id' => $this->item->getProduct()->getId(),
'product_name' => $productName,
'product_sku' => $this->item->getProduct()->getSku(),
'sort_description'=>'sort_description',
'product_url' => $this->getProductUrl(),
'product_has_url' => $this->hasProductUrl(),
'product_price' => $this->checkoutHelper->formatPrice($this->item->getCalculationPrice()),
'product_price_value' => $this->item->getCalculationPrice(),
'product_image' => [
'src' => $imageHelper->getUrl(),
'alt' => $imageHelper->getLabel(),
'width' => $imageHelper->getWidth(),
'height' => $imageHelper->getHeight(),
],
'canApplyMsrp' => $this->msrpHelper->isShowBeforeOrderConfirm($this->item->getProduct())
&& $this->msrpHelper->isMinimalPriceLessMsrp($this->item->getProduct()),
];
}
And override this file in your theme
/Magento_Checkout/web/template/minicart/item/default.html
and add below code in file
<div class="sort-description" data-bind="html:sort_description"></div>
You will sure get description in minicart