Hi,
Accents aren't hard. Add a .accent prop on the player, set it to whatever you like. In the verb :say, set it to say that the player speaks with this accent. For example:
this.location:announce_all(player:titlec(), " says in a ", player.accent, " accent, ", argstr);
Scents would be done the same way, accept you'd have to code a sniff/smell verb on $thing. Simply set it to say "this has no scent" if the property is blank.
I am, of coure, assuming you know some MOO code. If not, I would point you to this site, as it contains some very useful tutorials.