Astarion's accent is Transatlantic....which is a manufactured American accent mostly associated with old money types.
It really isn't. It is hyperbolic RP (Received Pronunciation); the vowel quality is way off in order to be Transatlantic. Listen to an actual Transatlantic accent; it only sounds vaguely similar. Obvious instances would be the way god(s) is pronounced; in transatlantic it would still be /gɑːdz/ but in Asteron's case it is obviously NOT that; he very clearly says /ɡɒdz/. There are plenty of other examples. Most versions of Transatlantic are also lightly rhotic whereas Astarion's is not at all. He CLEARLY has a British accent, a hyperbolic one, but a British one nonetheless.
