The game contains both Azure Striker Gunvolt and Azure Striker Gunvolt 2 packaged together with all the first games DLC and a new song.
The Switch version runs at 60 fps, has a new UI, has all previous dlc for both games from the 3DS, has a new theme song, and game play improvements like re-balancing difficulty and changing the Kudos system from the first game to the one used in the second.