She has the same specials as Marth, though I would assume they have some different properties (her dancing sword and dolphin slash seemed different to me, but I'm not a big Marth player so the exact differences aren't exactly clear in my mind).
Her u-air looked visually similar if not visually identical (again, not a big Marth player) to Marth's. Her nair, however, looks significantly different to me, unless I'm going insane. If you take a look at this gif http:// gfycat.com/ FineSentimentalGecko, I hope you'll see what I'm talking about. To me, it looks like her nair is NOT a "double slash" with two hits - one forward, one behind - like Marth's is, but rather is more of a multihit "spinning slash."
To me, the progression of the move looks like it hits:
Forward, hits Samus
Backward, hits no one
Forward, hits Samus again
Backward, hits Greninja
Then she brings it forward again for a sweep to bring it back around to the front. Not sure if this part has a hitbox though. IIRC, Marth should only have two hits on his nair and more ending lag.
I could be wrong for sure, though - like I've said, not huge on Marth so it could still be identical and I'm just missing it since I don't know him well enough.