Guest Author – How to display posts on /author archive page

UPDATE

I’m kinda getting there. So far I’ve managed to write a custom author posts link if a guest author exists.

The resulting URL for a post author and guest author now have matching formats …

post author ex: https://www.example.com/author/john-doe guest author ex: https://www.example.com/author/jane-doe

Now I just need to figure out how to hijack the author archive page to display posts from the post author OR the guest author.

FUNCTIONS.PHP CODE:

add_filter( 'the_author_posts_link', 'custom_author_posts_link' );

function custom_author_posts_link($url) {

global $post;

$post_object = get_field('post_author');

if ( $post_object ) {

// GUEST AUTHOR EXISTS - override post object to grab relevant guest author info
global $post;
$post = $post_object;
setup_postdata( $post );

$guest_author_slug = $post->post_name;
$guest_author_name = get_field('team_member_name');
$guest_author_posts_link = site_url() . '/author/' .  $guest_author_slug;

$guest_url = sprintf(
    '<a href="%1$s" title="%2$s" rel="author">%3$s</a>',
    esc_url( $guest_author_posts_link ),
    esc_attr( sprintf( __( 'Posts by %s' ), $guest_author_name ) ),
    $guest_author_name
);

$guest_url = $link; 

wp_reset_postdata(); // We're done here. Return to main $post object

}

return $url;

}

I ended up going with the Co-Authors Plus plugin. It still was a bit challenging, but this plugin achieved all that I needed to: https://www.ads-software.com/plugins/co-authors-plus/