The white one, assuming you're that height and that dress looks like that on you, is too short.
The red one is fine, but you'd expect to wear something with sleeves over it.
The green dress is very suitable, but again, you'd expect to wear something with sleeves over it (e.g. a blazer or cardigan that you could take off).
The black dress is a no, even for evenings. You'd expect to wear something that goes from day into evening, not something that you clearly couldn't wear during the day. When you work in the City, you work long hours, and you don't have time to change. You have to be able to adapt your day outfit into a night outfit.
The playsuit is an outright no if you're working for a traditional City firm. You'd have to be working for someone really fun for that to be acceptable. (A much smaller list of places.)
I don't mind the cold, but I think you'd find coming from Australia that you would want to layer up and/or wear things with sleeves anyway. It's not entirely that flesh is scandalous; it's more that it's usually too damn cold in the City to show that much!