Preloading Advanced Custom Fields Pro license key https://anchor.host/2017/05/16/preloading-advanced-custom-fields-pro-license-key/

preload_acf_pro_key.php

// Preload ACF key from wp-config.php into database
function anchor_acf_auto_set_license_keys() {

  // Check if ACF is running and ACF Pro key found in wp-config.php
  if ( class_exists('acf') && defined('ACF_PRO_KEY') ) {

    $save = array(
            'key'   => ACF_PRO_KEY,
            'url'   => home_url()
        );

        $save = maybe_serialize($save);
        $save = base64_encode($save);

    update_option('acf_pro_license', $save);
  }
}

// Runs 'Preload ACF key' if WP-CLI runs a search-replace
if ( defined( 'WP_CLI' ) && WP_CLI ) {
    WP_CLI::add_hook( 'after_invoke:search-replace', 'anchor_acf_auto_set_license_keys' );
}