Here is the full list of all 17 Aqua Moto Racing Utopia (EU) trophies - there are 3 bronze, 4 silver, 9 gold and 1 platinum.
Find the ball of straw at each Venue
In a Championship race, pass every buoy in 1st place and win
Perform a Backflip with a Runabout watercraft
Perform 20 stunts during a Freestyle Event
Win every Ski Championship
Win every Runabout Championship
You must pass each buoy perfectly in a Championship race
Win a Championship event
Jump over 40m
Complete the tutorial
Complete all other Trophies
Own every watercraft
Win gold medals in Time Trial mode on every Track
Win the gold medal in all Freestyle events
Perform every stunt at least once in a race
Perform every air stunt at least once in a Freestyle Event
Perform every water stunt at least once in a Freestyle Event