Suggestions by @sadsamurai

Fred Tatasciore

as Sergeant Detritus in Jingo

Terence Hill

as Sergeant Fred Colon in Jingo

Liam Neeson

as Captain Carrot Ironfoundersson in Jingo

Ray Abruzzo

as Lord Havelock Vetinari in Jingo

Ayushmann Khurrana

as Prince Cadram in Jingo

Ewan McGregor

as Lord Rust in Jingo

Saif Ali Khan

as 71-Hour Ahmed in Jingo

Jay Acovone

as Commander Sam Vimes in Jingo

Mammootty

as Prince Khufurah in Jingo

Khaled El Nabawy

as Nylonathatep in Discworld Noir

Jimmy Jean-Louis

as Anu-Anu in Discworld Noir

Elden Henson

as Gaspode in Discworld Noir

Shawn Dou

as Two-Conkers in Discworld Noir

Lady Gaga

as Therma in Discworld Noir

Whoopi Goldberg

as Sapphire in Discworld Noir

David Duchovny

as Horst in Discworld Noir

Chinedu Ikedieze

as Al-Khali in Discworld Noir

Jay Acovone

as Commander Sam Vimes in Discworld Noir

50 Cent

as Malachite in Discworld Noir

Alicia Keys

as Ilsa in Discworld Noir