Contextual filter node title as autocmplet

Normally entity autocomplete form element is used for setting entity id, not the title. So out of the box, it is not possible. But it is always possible to create your own autocomplete element that will return title instead of id (btw, entity autocomplete that is used in the dialogs is Drupal core element, this module has nothing to do with its functionality) and then later use that element in the dialog form with form alter hook.