Are there any English/British actresses that can do American accents?
I think it’s some sort of bias in people who speak British (me included) to think they’re actually doing a great job. Maybe they are, maybe they actually aren’t: as we’re no experts in Yank accents, we may be impressed ‘easier’ by some apparent accuracy in their portrayal, but an actual American could think ‘that’s not us’. The opposite thing does happen a lot: ‘x’ American actor does a pseudo-British accent, Yank audiences are wowed, people in Britain say ‘WTF?’. Same for other accents such as South African, Indian, etc. Although not an actress, I think KT Tunstall does a (for me, and I’m no expert in American accents) fairly good Yank when she wants to. There’s also that Mancunian lady who was in ‘Pushing Daisies’, very believable American accent for my ears (which are obviously biased).