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