Here is the full list of all 42 Persona 5: Dancing in Starlight trophies - there are 26 bronze, 12 silver, 3 gold and 1 platinum.
Obtained all trophies.
Watched every possible dance for Futaba.
Watched every possible dance for the P5 Protagonist (Ren Amamiya).
Watched a replay.
Cleared a stage with 5 Challenge and 5 Support modifiers simultaneously enabled.
Obtained all the costumes.
Watched all Social events.
Obtained all rewards from the Twins' card hunt.
Cleared a stage after changing Hype Gauge difficulty in Custom.
Cleared a stage with both "Note paths waver" and "Note speed fluctuates" enabled.
Cleared a stage with both "GOOD ratings won't break combos" and "Game Over with combo break" enabled.
Obtained all the accessories.
Unlocked all Custom modifiers.
Started a stage on ALL NIGHT difficulty with 10 or more Challenge modifiers enabled.
Registered a costume as a Favorite.
Obtained all the pairs of glasses.
Explored all the guys' rooms.
Had the Twins join the grand ball.
Obtained an invaluable treasure upon the stage.
Explored all the girls' rooms.
Cleared a stage on HARD or harder with all Support modifiers enabled.
Watched 40 different Fever Time dances.
Cleared a stage on HARD or harder and earned a PERFECT rating on at least half of the Notes.
Started a stage with a different hairstyle, two accessories, color contacts, and a colored wig.
Obtained half of all the accessories.
Obtained 5 rewards from the Twins' card hunt.
Cleared the stages where Yusuke and Makoto dance together.
Cleared the stages where Ryuji and Ann dance together.
Failed a stage.
Cleared the stages where Morgana and Haru dance together.
Explored a friend's room.
Unlocked the highest difficulty level (ALL NIGHT).
Obtained half of all the costumes.
Unlocked all ???s in Collection.
Watched 20 Social events.
Changed costumes and played a stage with each of the Phantom Thieves (excluding Akechi).
Beat your own high score.
Watched a Social event.
Cleared a stage.
Earned the highest possible grade on a stage (KING CRAZY).
Played a tutorial.
Obtained a costume.