Here is the full list of all 46 The Seven Deadly Sins: Knights of Britannia trophies - there are 34 bronze, 8 silver, 3 gold and 1 platinum.
Unlocked all characters.
Settled things with Zeldris.
Defeated Albion.
Completed all quests in eastern Liones.
Found Magic Crystals on the field map 100 times.
Escanor joined your team.
All Seven Deadly Sins assembled.
Merlin joined your team.
Defeated Hendrickson after he attained the Ash Demon's power.
Used 100 magic traps.
Got a total of 100,000 Magic Crystals.
Settled things with Gilthunder.
Acquired 100% of an area's Gossip Points.
Gowther joined your team.
Meliodas awakened his demon power.
King joined your team.
Ban joined your team.
Won a battle with no damage.
Used a Special Move.
Diane joined your team.
Landed a 30-hit combo.
Fought with a Magic Item equipped.
Completed first side quest.
Explored the Britannian map for the first time.
Created a Magic Item.
Quest "The Boar Hat" completed.
All trophies acquired. Congratulations!
Completed all main quests with "S" rank.
Completed all side quests.
Completed all side quests with "S" rank.
Completed all errand quests.
Completed all quests in western Liones.
Completed all quests in central Liones.
Completed all quests in southern Liones.
Completed all quests in northern Liones.
Completed all quests in the capital city.
Completed all quests.
Completed all quests with "S" rank.
Acquired 100% of Gossip Points for all of Liones.
Maxed out HP for all members of the Boar Hat crew.
All combat-type Magic Items created.
All adventure-type Magic Items created.
All Boar Hat abilities enhanced.
Created all Magic Items.
Landed a Co-Op Attack with a partner.
Used Special Moves for all characters.