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.
Cross the Bridge door in less than 3 hours.
Talk with all the corpses.
Get all prayers.
Get 100% of the game.
Release all cherubs.
Bring all the offerings to Lvdovico.
Get all collectibles.
Get all sword hearts.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Achieve the maximum value of flasks.
Unlock the ending A.
Get all rosary beads.
Beat all the arena challenges.
Achieve the maximum value of fervor.
Use the Righteous Riposte 5 times.
Buy all the items of the Candelaria shops.
Achieve the maximum value of rosary bead slots.
Visit the tomb of The Lady of the Tailed Gown.
Achieve the maximum value of health.
Help Cleofás in his path of redemption.
Buy all skills from the Mea Culpa shrines.
Achieve the maximum level of the Mea Culpa sword.
Help the Pilgrim reach his final destination.
Hatch the Egg of Altasgracias.
Save all Kissers of Wounds.
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.
Beat Quirce, Returned by the Flames.
Beat Melquíades, The Exhumed Archbishop.
Beat Exposito, Scion of Abjuration.
Execute 5 different enemies.
Kill 666 enemies.
Beat Esdras, of the Anointed Legion.
Witness the last moments of Viridiana.
Beat the Our Lady of the Charred Visage.
Beat the Tres Angustias.
Beat Perpetua.
Beat Ten Piedad.
Beat the Warden of the Silent Sorrow.