The director and screenwriter of "sharp visors" Steve Knight revealed The Guardian some of their considerations associated with the sixth season of the series. Since the series is very popular, then many Stars of Hollywood are associated with his creator in the hope of getting a role in the project.
This is what Steve Knight said about this:
With us, a large number of people willing to participate in the project. Among them, Brad Pitt, Snup Dog, a $ AP Rocky and others. I think that in the sixth season we have some famous actors call in the "sharp visors". But it is important to be professional here. For each new character of the series, we will look for an actor who will play it in the best way, as we did with Sam Claflin, who played Mosley.
We managed to be fine. But I am definitely against small kameo stars. Bad, when the actor appears on the screen only for the time that the audience recognized him. Such a situation will distract from the plot and will not go for the good of the TV series. Examples of victims from chamber serials are quite numerous.
So, judging by Steve Knight, rappers may want to get into the series, but they have no chance of role like that Ed Shiran in the "Game of Thrones".