improvements-2.x-dev/modules/improvements_taxonomy/improvements_taxonomy.routing.yml

entity.taxonomy_term.delete_multiple_form:
  path: '/admin/structure/taxonomy/delete-terms'
  defaults:
    _form: '\Drupal\improvements_taxonomy\Form\TermDeleteMultipleConfirmForm'
    entity_type_id: 'taxonomy_term'
  requirements:
    _entity_delete_multiple_access: 'taxonomy_term'