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