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