Here is the full list of all 29 Slipstream achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Defeat Norman in Parthenon.
Defeat David in Neon City.
Defeat Alex in Metropolis.
Win a cannonball race of all 5 secret tracks, in any order
Complete everything.
Win a cannonball race of all 5 nighttime tracks, in any order.
Defeat Tofu Boy in Akagiyama.
Reach every exit defeating all the rivals along the way.
Complete all possible routes in Arcade Mode.
Defeat every rival character in Arcade Mode at least once.
Win all the races in all cups.
Win a race with every car model in Quick Race Mode.
Win the Diamond Cup.
Win the Emerald Cup.
Win the Sapphire Cup.
Defeat Camilla in Highgate Cemetery.
Win all the races in any cup.
Win the Ruby Cup.
Win a race in Grand Prix mode without any car upgrades.
Win a battle royale match.
Win a cannonball race of 15 tracks.
Defeat all the rivals in a cannonball race of 5 or more tracks.
Win a cannonball race of 5 or more tracks.
Stay on the slipstream for more than 15 seconds in any mode.
Defeat all the rivals in a single Arcade Mode run.
Visit all the tracks in Arcade Mode.
Get to all the exits in Arcade Mode.
Complete a stage in arcade mode without touching anything.
Get to the finish line in Arcade Mode.