Two descriptions from Fanny Burney and Mary Berry, both from 1802:

Fanny Burney:

Napoleon's face 'is of a deeply impressive cast, pale even to sallowness, while not only in the eye but in every feature-care, thought, melancholy, and meditation are strongly marked, with so much of character, nay, genius, and so penetrating a seriousness, or rather sadness, as powerfully to sink into an observer's mind...far more the air of a student than a warrior.'

Mary Berry:

Napoleon's 'mouth, when speaking...has a remarkable and uncommon expression of sweetness. His eyes are light grey, and he looks full in the face of the person to whom he speaks. To me always a good sign.'