Add an ACF field after shop item title on Shop or Product Category page template

functions.php

<?php
add_action('woocommerce_after_shop_loop_item_title', 'add_custom_product_info', 18);
function add_custom_product_info() {
  global $product;
  $product_unit_price = get_field('unit_price', $product->id);
  // Displaying the custom field only when is set with a value
  if(!empty($product_unit_price )) {
	  // Change text-domain with your own.
	  echo '<p style="color: red; font-weight: 600; font-size: 1.2rem">' . __('Ab ', 'text-domain') . $product_unit_price . '€ / Stück</p>';
  }
}