Here is the full list of all 15 Bloodstained: Curse of the Moon achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Defeat every boss in Boss Rush mode.
Finish the game without sacrificing or recruiting any adventurers.
Sacrifice every adventurer and finish the game.
Go it alone and see the Normal ending.
Adventure with your allies and see the Normal ending.
Finish Nightmare Mode.
Recruit every adventurer and finish the game.
Finish Stage 8 for the first time.
Finish Stage 7 for the first time.
Finish Stage 6 for the first time.
Finish Stage 5 for the first time.
Finish Stage 4 for the first time.
Finish Stage 3 for the first time.
Finish Stage 2 for the first time.
Finish Stage 1 for the first time.