Drupal 8 create a template override for a view block within a custom module
To get the same variables as a block template add it as base hook:

/**
 * Implements hook_theme().
 */
function mymodule_theme() {
  return [
    'block__views_block__MYVIEW_block_1' =&gt; [
      'render element' =&gt; 'elements',
      'base hook' =&gt; 'block',
    ],
  ];
}


Now you can place the twig template in mymodule/templates/, path and filename are discovered automatically.