Hi,

So I saw this thread (first link at the very bottom) which response was
to use a couple of functions. So the thing is that I evaluated the
functions, and supposedly it should something like \ast when executing
C-u *, but it doesn't happen. Any idea on what I could be doing wrong?

The functions are:

(defun modi/org-entity-get-name (char)
  "Return the entity name for CHAR. For example, return \"ast\" for *."
  (let ((ll (append org-entities-user
                    org-entities))
        e name utf8)
    (catch 'break
      (while ll
        (setq e (pop ll))
        (when (not (stringp e))
          (setq utf8 (nth 6 e))
          (when (string= char utf8)
            (setq name (car e))
            (throw 'break name)))))))

(defun modi/org-insert-org-entity-maybe (orig-fun &rest args)
  "When the universal prefix C-u is used before entering any character,
insert the character's `org-entity' name if available."
  (let ((pressed-key (this-command-keys))
        entity-name)
    (when (and (listp args) (eq 4 (car args)))
      (setq entity-name (modi/org-entity-get-name pressed-key))
      (when entity-name
        (setq entity-name (concat "\\" entity-name "{}"))
        (insert entity-name)
        (message (concat "Inserted `org-entity' "
                         (propertize entity-name
                                     'face 'font-lock-function-name-face)
                         " for the symbol "
                         (propertize pressed-key
                                     'face 'font-lock-function-name-face)
                         "."))))
    (when (null entity-name)
      (apply orig-fun args))))

(advice-add 'org-self-insert-command :around
#'modi/org-insert-org-entity-maybe)


https://emacs.stackexchange.com/questions/16688/how-can-i-escape-the-in-org-mode-to-prevent-bold-fontification

Regards