edlp_d8/web/modules/custom/edlp_agenda/edlp_agenda.module

<?php

/**
 * Implements hook_theme().
 */
function edlp_agenda_theme($existing, $type, $theme, $path) {
  // @see https://www.drupal.org/docs/8/theming/twig/create-custom-twig-templates-from-custom-module
  return array(
    'edlp_agenda' => array(
      // 'render element' => '',
      'file' => 'includes/edlp_agenda.inc',
      'variables' => array(
        'next_event_node' => NULL,
        'coming_events_nodes' => NULL,
        'past_events_nodes' => NULL
      ),
    ),
  );
}