Okay anyone wanting to achieve this, the code works. Just save the values in the custom field without quotes. e.g. red, car
<?php
$list = get_field( "main_attributes" );
$array = explode(',', $list);
$args = array(
'meta_query' => array(
'relation' => 'OR',
array(
'key' => 'style_atrributes',
'value' => $array,
'compare' => 'IN'
),
array(
'key' => 'car_atrributes',
'value' => $array,
'compare' => 'IN'
),
),
);
$custom_query = new WP_Query($args);
while($custom_query->have_posts()) : $custom_query->the_post(); ?>
<div <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<h1><a href="https://wordpress.stackexchange.com/questions/188449/<?php the_permalink(); ?>"><?php the_title(); ?></a></h1>
<?php the_content(); ?>
</div>
<?php endwhile; ?>
<?php wp_reset_postdata(); // reset the query ?>