Here is the full list of all 51 MotoGP 20 trophies - there are 38 bronze, 10 silver, 2 gold and 1 platinum.
Unlock all trophies
Complete 25 valid laps in Time Trial mode
Complete 5 valid laps in Time Trial mode
Win a race at Donington in Grand Prix or Championship mode
Win a race at Laguna Seca in Grand Prix or Championship mode
Win a race at Valencia in Grand Prix, Championship or Career mode
Win a race at Sepang in Grand Prix, Championship or Career mode
Win a race at Phillip Island in Grand Prix, Championship or Career mode
Win a race at Motegi in Grand Prix, Championship or Career mode
Win the MotoGP™ Championship in Career mode as a rider
Complete 10 races with Tire Wear and Fuel Consumption in Grand Prix, Championship or Career mode
Complete at least 3 valid laps in a Winter Test session in Career mode
Win the Moto2™ Championship in Career mode as a rider
Win a race at Buriram in Grand Prix, Championship or Career mode
Reach the Race objective 20 times in Career mode
Reach the Qualifying objective 20 times in Career mode
Win a race at Aragon in Grand Prix, Championship or Career mode
Win the Moto3™ Championship in Career mode as a rider
Win a race at Misano in Grand Prix, Championship or Career mode
Win a race at Silverstone in Grand Prix, Championship or Career mode
Win a race at Spielberg in Grand Prix, Championship or Career mode
Complete 10 Development Tests in Career mode
Win a race at Brno in Grand Prix, Championship or Career mode
Win a race at KymiRing in Grand Prix, Championship or Career mode
Reach the Race objective 10 times in Career mode
Reach the Qualifying objective 10 times in Career mode
Complete 5 Development Tests in Career mode
Win a race at Assen in Grand Prix, Championship or Career mode
Unlock every Rider and Team in Historic Mode
Complete a Development Test in Career mode
Win a race at Catalunya in Grand Prix, Championship or Career mode
Unlock 40 rewards in Historic Mode
Win a race at Mugello in Grand Prix, Championship or Career mode
Complete 25 multiplayer races
Complete 10 multiplayer races
Complete 5 multiplayer races
Complete your first multiplayer race
Win a race at Le Mans in Grand Prix, Championship or Career mode
Reach the Race objective 5 times in Career mode
Reach the Qualifying objective 5 times in Career mode
Unlock 20 rewards in Historic Mode
Win a race at Jerez in Grand Prix, Championship or Career mode
Win 10 races in Historic Mode
Unlock 10 rewards in Historic Mode
Win a race at Termas in Grand Prix, Championship or Career mode
Win a race at Sachsenring in Grand Prix, Championship or Career mode
Win a race at Austin in Grand Prix, Championship or Career mode
Win a race at Losail in Grand Prix, Championship or Career mode
Obtain the Pole Position in Grand Prix, Championship or Career mode
Obtain access to Qualifying 2 in Grand Prix, Championship or Career mode
Win a race in Historic Mode