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