His portraits use a formalised Baroque style. He focused on the physical textures of clothing. He also captured the specific facial features of his subjects. In the portrait of Michael Willmann, Heckenauer depicts the sitter with a direct gaze and clear lines. He avoided the over-elaborate backgrounds common in later periods. Instead, he used simple oval frames or architectural borders to keep the attention on the individual. This clarity makes his engravings easy to read.

The monochrome nature of these 17th-century engravings fits with modern interior design. Collectors appreciate the historical weight of figures like Anselm Franz von Ingelheim or Anna Christina Heiland. These prints provide a sense of history without the visual clutter of multi-coloured works. They offer a connection to the craftsmanship of the Augsburg school. The sharp contrast and clean execution of his copperplates remain visually striking.