#+begin_src elisp :noexport
(defun my-set-property-at-heading ()
  "Function to be called at the beginning of an Org heading."
  (interactive)
  (let ((el (org-element-at-point)))
    (org-set-property "New" (org-element-property "[ ]" el)))))
(org-map-entries #'my-set-property-at-heading)

#+end_src