Hi @Conor_Lorimer,
You may want to have a look at this thread regarding roles as “permanent” email aliases:
Asana does have a “Role” field each user can assign themselves:
but currently it’s only used to filter in a couple of places really, I believe.
To be able to use the role as the assignee (and collaborator) is, I feel, the most direct way, but as @Justin.Koetsier says, that requires an alias and Asana login.
Larry