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