Here is the full list of all 45 Blasphemous achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Unlock the ending A.
Get all collectibles.
Beat all the arena challenges.
Get all rosary beads.
Get all sword hearts.
Bring all the offerings to Lvdovico.
Achieve the maximum value of rosary bead slots.
Achieve the maximum value of fervor.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Visit the tomb of The Lady of the Tailed Gown.
Achieve the maximum level of the Mea Culpa sword.
Help Cleofás in his path of redemption.
Achieve the maximum value of health.
Help the Pilgrim reach his final destination.
Hatch the Egg of Altasgracias.
Unlock the ending B.
Beat His Holiness Escribar.
Beat Crisanta of the Anointed Blade.
Buy all the items of the Candelaria shops.
Beat Quirce, Returned by the Flames.
Beat all types of enemies.
Beat Exposito, Scion of Abjuration.
Execute 5 different enemies.
Discover all zones.
Beat Melquíades, The Exhumed Archbishop.
Beat Esdras, of the Anointed Legion.
Beat the Tres Angustias.
Kill 666 enemies.
Beat Ten Piedad.
Beat Perpetua.
Beat the Our Lady of the Charred Visage.
Beat the Warden of the Silent Sorrow.
Release all cherubs.
Talk with all the corpses.
Get all prayers.
Achieve the maximum value of flasks.
Use the Righteous Riposte 5 times.
Witness the last moments of Viridiana.
Save all Kissers of Wounds.
Buy all skills from the Mea Culpa shrines.
Provoke the meeting between Redento and Cleofás.
Beat all bosses without flask consumption.
Cross the Bridge door in less than 3 hours.
Get 100% of the game.