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