Here is the full list of all 45 Blasphemous achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Get all prayers.
Get all collectibles.
Release all cherubs.
Unlock the ending A.
Achieve the maximum value of flasks.
Bring all the offerings to Lvdovico.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Buy all skills from the Mea Culpa shrines.
Achieve the maximum value of rosary bead slots.
Visit the tomb of The Lady of the Tailed Gown.
Achieve the maximum level of the Mea Culpa sword.
Help the Pilgrim reach his final destination.
Beat all the arena challenges.
Beat Quirce, Returned by the Flames.
Beat all types of enemies.
Unlock the ending B.
Beat His Holiness Escribar.
Discover all zones.
Beat Crisanta of the Anointed Blade.
Hatch the Egg of Altasgracias.
Help Cleofás in his path of redemption.
Beat Melquíades, The Exhumed Archbishop.
Buy all the items of the Candelaria shops.
Beat Exposito, Scion of Abjuration.
Beat Esdras, of the Anointed Legion.
Witness the last moments of Viridiana.
Beat the Our Lady of the Charred Visage.
Kill 666 enemies.
Beat the Tres Angustias.
Beat Ten Piedad.
Beat the Warden of the Silent Sorrow.
Talk with all the corpses.
Get all rosary beads.
Get all sword hearts.
Achieve the maximum value of health.
Achieve the maximum value of fervor.
Execute 5 different enemies.
Use the Righteous Riposte 5 times.
Save all Kissers of Wounds.
Beat Perpetua.
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.