WooCommerce - Display custom attributes on shop page - the official way ;-)

content-product.php

// Paste this in your file, somewhere in the loop, around the h3
<?php echo $product->sku; ?> <?php echo $product->omschrijving; ?> <?php the_title(); ?>

<?php
// Get the attributes
$attributes = $product->get_attributes();
// Start the loop
foreach ( $attributes as $attribute ) : ?>

<?php
// Check and output, adopted from /templates/single-product/product-attributes.php
    if ( $attribute['is_taxonomy'] ) {
        $values = wc_get_product_terms( $product->id, $attribute['name'], array( 'fields' => 'names' ) );
        echo apply_filters( 'woocommerce_attribute', wpautop( wptexturize( implode( ', ', $values ) ) ), $attribute, $values );
    } else {
        // Convert pipes to commas and display values
        $values = array_map( 'trim', explode( WC_DELIMITER, $attribute['value'] ) );
        echo apply_filters( 'woocommerce_attribute', wpautop( wptexturize( implode( ', ', $values ) ) ), $attribute, $values );
    }
?>

<?php endforeach; ?>

Thank you )