Add a post author link to a Post Author Listing Builder item

<?php

// Set your Post Author Listing Builder item's 'Author field' setting to 'User ID'.
// Replace 'my-author-item' with the 'Unique name' of your Post Author builder item.

add_filter( 'facetwp_builder_item_value', function( $value, $item ) {

  if( $item['settings']['name'] == 'my-author-item' ) {

    $author_id = $value;
    $author_link = get_author_posts_url( $author_id );
    $author_name = get_the_author_meta( 'display_name', $author_id );

    return '<a href="' . $author_link . '">'. $author_name . '</a>';
    
  }
  return $value;

}, 10, 2 );