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