How do you exclude 'drush' & 'drupal console' requirements from a drupal-composer/drupal-project install?
You can remove these after the fact:

composer remove drush/drush
composer remove drupal/console


However, it is recommended that you should use local installs of Drush and Drupal Console when using Drupal 8. If you use global versions of these tools, then you run the risk of running into dependency hell - incompatibilities between requirements of Drush or Drupal Console that do not align with what is used in Drupal 8.  When you use a global cli tool to bootstrap Drupal 8, then the cli tool will load two autoloaders.  If the same library exists in both autoloaders at different versions -- even just a "dot release" difference -- then you could get into a situation where every command aborts with an unrecoverable error.

If you only maintain a single version of Drupal 8 on your system, and carefully keep the versions of Drush and Drupal Console in alignment with that, then it will typically work, so you may remove the local version if you wish. The diagnostic efforts required when something goes wrong is quite extensive, so be cautious if you make this choice.