Strider from the Marvel vs. Capcom series and Chipp from the Guilty Gear series.
Both characters are based around ninjas, and revolve around extreme speed, quick projectiles, and teleportation in their gameplay style. However, the way Greninja handles his water blades is more reminiscent of Chipp. But both characters suffer from having low health and below normal power, though the latter is normally compensated by high combo capabilities.
Greninja's Final Smash is based on Strider's Ragnarok attack in particular.
However going solely by Super Smash Bros., his high falling speed is similar to Captain Falcon and the spacies, while his high jump reminds me of Sheik.