If DD is < 3 secs to 1b, even if she is a natural righty, then slapping could be an effective tool in the kit. Slower than that and stick with power from the right.
I agree that it should ideally be a naturally left handed kid with great speed, however the best slapper on my team is a right hander with speed. But her right handed mechanics are horrible due to years of slow pitch. So I converted her to a short game player on the left and she took to it like a fish in water.
If your dd is a right handed power hitter, I'd leave it alone.