Copying field values from one EntityForm to another on submit
If you don't mind using query parameter for passing value. Prepopulate would be your choice.

Example code:

function extra_inschrijving_default_wp_submit($form, &amp;$form_state){
  $values = &amp;$form_state['values'];
  $prepopulates = array(
    'edit[title]' =&gt; $values['title'],
  );
  $form_state['redirect'] = array(
    'node/add/article',
    array(
      'query' =&gt; $prepopulates,
    ),
  );
}


$prepopulates is an array for query parameter which will pass the pre-filled values to the node add form. The array keys specify the fields prepopulate to. You can learn how to set the key from the handbook page.

At this moment, the latest stable version 2.1 has a known bug and it is discussing here. If you the module is not working on some field, you may need to add the patch in the thread. I don't recommend the older stable version because 2.1 has fixed an exploit.