The standard English accent indicates that the General will likely be in the service of a Southerner.
All of these one-weekers aside from the Lovely Lady and the Merchant are intended to be played by white actors with standard English accents.
The Merchant and the Lovely Lady roles do not seem to require a certain accent or race, so they’ll probably hail from one of the diverse cities of Essos.
The descriptions as listed by Watchers on the Wall will hopefully be enough to tide Game of Thrones fans over for the time being.