mercury_editor-2.0.x-dev/modules/mercury_editor_templates/mercury_editor_templates.links.menu.yml

entity.me_template.settings:
  title: 'Mercury Editor Template'
  description: 'Configure a Mercury Editor Template entity type.'
  route_name:  entity.me_template.settings
  parent: system.admin_structure
entity.me_template.collection:
  title: 'Mercury Editor Templates'
  description: 'List of Mercury Editor templates.'
  route_name: entity.me_template.collection
  parent: system.admin_content