org-export-preprocessor.el

      (defun jdiez/org-roam--backlinks-list (file)
        (--reduce-from
         (concat acc (format " - [[file:%s][%s]]\n\t - %s\n"
			     (file-relative-name (car it) org-roam-directory)
			     (org-roam--get-title-or-slug (car it))
			     (plist-get (car (cdr it)) :content)))
          "" (org-roam-sql [:select [file-from, properties] :from file-links :where (= file-to $s1)] file)))
      
      (defun jdiez/org-export-preprocessor (backend)
        (let ((links (jdiez/org-roam--backlinks-list (buffer-file-name))))
          (unless (string= links "")
            (save-excursion
      	     (goto-char (point-max))
      	     (insert (concat "\n* Backlinks\n") links)))))
      
      (add-hook 'org-export-before-processing-hook 'jdiez/org-export-preprocessor)