Microsoft's initiative to allow games from the original Xbox to work with their Xbox One systems will begin tomorrow with 13 games; one of them being one of the more uncommon games in The King of Fighters series.
The King of Fighters Neowave was chosen along with more recognizable hits such as Star Wars: Knights of the Old Republic, Ninja Gaiden Black, Psychonauts and Prince of Persia: The Sands of Time as the first set of backwards compatible original Xbox games. These games, and others in the future, are made to work with Microsoft's latest systems, including the upcoming Xbox One X.
According to IGN's Ryan McCaffery, these games have been "enhanced with 1080p resolution, higher and/or smoother framerates, and faster loading times." While there is no direct comparison for Neowave specifically, IGN's article does have some videos showing some changes to other games to give you an idea of the enhancements. Latency hasn't been addressed in the article. Some of these games, including Neowave, had Xbox Live support but due to the service shutting down in 2010, the featured games lack this online ability.
With Neowave being part of this initial run of backwards compatible Xbox games, there are some more KOF and other SNK fighting games that haven't been given the updated treatment yet. The original Xbox also carried other fighters such as Soulcalibur II, Capcom vs. SNK 2 EO, Capcom Fighting Evolution and Street Fighter Anniversary Collection that can potentially come to the backwards compatibility list in the future.