Here is the full list of all 45 Blasphemous achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Release all cherubs.
Beat His Holiness Escribar.
Unlock the ending B.
Bring all the offerings to Lvdovico.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Discover all zones.
Beat Crisanta of the Anointed Blade.
Achieve the maximum value of rosary bead slots.
Help the Pilgrim reach his final destination.
Achieve the maximum value of health.
Beat Quirce, Returned by the Flames.
Beat all types of enemies.
Beat Melquíades, The Exhumed Archbishop.
Buy all the items of the Candelaria shops.
Beat Exposito, Scion of Abjuration.
Visit the tomb of The Lady of the Tailed Gown.
Hatch the Egg of Altasgracias.
Beat the Tres Angustias.
Kill 666 enemies.
Beat Perpetua.
Beat Ten Piedad.
Execute 5 different enemies.
Beat the Our Lady of the Charred Visage.
Beat the Warden of the Silent Sorrow.
Beat Esdras, of the Anointed Legion.
Unlock the ending A.
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.
Use the Righteous Riposte 5 times.
Witness the last moments of Viridiana.
Help Cleofás in his path of redemption.
Save all Kissers of Wounds.
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.