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