Pull out Advanced Custom Fields in Related post plugin

According to advenced custom fields you get the value with get_field http://www.advancedcustomfields.com/docs/functions/get_field/

Just change “text_field” to your field-key.

<?php
$related = MRP_get_related_posts( $post->ID, true, false, 'quote_list' );

if( !empty( $related ) ) {
    foreach( $related as $key => $value ) { 

        // Get post
        $related = get_post( $value );

        // Get the field "text_field" on all posts
        $value = get_field( "text_field", $related->ID  );

        $output="<div><h4>";
            $output .= get_the_title( $related->ID );
        $output .= '</div></h4>';

        // print the value from ACF

        if( $value ) {
            $output .= $value;
        }

        $output .= $related->post_excerpt;

        $output .= '<a href="'. get_permalink( $related->ID  ) .'">'. __('Read more','domain') .'</a>';
    }

    // Echo 
    echo $output;
}