author-contact.php

<?php
/**
 * Core Functionality Plugin
 *
 * @package    CoreFunctionality
 * @since      1.0.0
 * @copyright  Copyright (c) 2014, Bill Erickson & Jared Atchison
 * @license    GPL-2.0+
 */

// Author Form
define( 'EA_AUTHOR_FORM_ID', 5192 );

// Author Field, hidden field in the form above
// In WPForms, set the default value to {query_var key="person"}
define( 'EA_AUTHOR_FIELD_ID', 3 );

/**
 * Adds author photo and name at top of form
 * @author Bill Erickson
 * @link http://www.billerickson.net/contact-form-dynamic-notification/
 *
 * @param array $form_data, form data
 */
function ea_author_on_form( $form_data ) {

	// Only run on the 'Contact an Author' form, and if an author is specified in the URL
	if( !( EA_AUTHOR_FORM_ID == $form_data['id'] && isset( $_GET['person'] ) ) )
		return;

	// Display author
	$person = intval( $_GET['person'] );
	$name = get_the_author_meta( 'display_name', $person );
	$photo = get_avatar( $person, 48 );
	echo '<h2 class="author">Contacting: ' . $photo . $name . '</h2>';

}
add_action( 'wpforms_frontend_output', 'ea_author_on_form', 9 );

/**
 * Use author email address
 * @author Bill Erickson
 * @link http://www.billerickson.net/contact-form-dynamic-notification/
 *
 * @param array $email, contains all the information used to build email notification (address, message...)
 * @param array $fields, form fields
 * @param array $entry, form entry
 * @param array $form_data, form data
 * @return array $email
 */
function ea_author_email_address( $email, $fields, $entry, $form_data ) {

	if( !( EA_AUTHOR_FORM_ID == $form_data['id'] ) )
		return $email;

	$author_id = false;
	foreach( $fields as $field ) {
		if( EA_AUTHOR_FIELD_ID  == $field['id'] ) {
			$author_id = intval( $field['value'] );
		}
	}

	if( $author_id ) {
		$email['address'] = array( get_the_author_meta( 'email', $author_id ) );
	}

	return $email;
}
add_filter( 'wpforms_entry_email_atts', 'ea_author_email_address', 10, 4 );