There isn't much of a difference to be honest, just that in the second you blurred the shadows.
I would recommend a third option:
With an Air brush in transparency, erase bits of the shadows, that way you can have both solid and soft ones.
Then when you finished the whole drawing, merge all layers or merge them in a new one, copy and paste it, the layer on top blurr it on the default of the program you're using, then lower the opacity to 30% that way it softens the lineart a bit and gives a smoother look.
Like this: