If you fixed her position (she needs to be lower IMO) and made her hair and skin look wetter, you could probably get away with it. People who see someone like that will automatically associate it with swimming first, if the environment is right (swimming pool instead of chemical works, for example :). You won't get photorealism without resorting to a third party renderer or post work, so it's probably best not to try if Poser is all you have.