materio-d8/web/modules/custom/materio_home/materio_home.module

<?php

/**
 * Implements hook_theme().
 */
function materio_home_theme($existing, $type, $theme, $path) {
  // @see https://www.drupal.org/docs/8/theming/twig/create-custom-twig-templates-from-custom-module

  return array(
    'materio_home' => array(
      // 'render element' => '',
      'file' => 'includes/materio_home.inc',
      'variables' => array(),
    ),
  );
}