His style relies on precise line work and clear compositions. Couvay often collaborated with other designers but brought his own sense of clarity to the final engraving. In works like Madonna with the Pink, he adapted Renaissance motifs with a French Baroque sensibility. He used cross-hatching to create depth and volume without relying on heavy shadows. This technique allowed him to produce prints that remained sharp even after multiple pressings. His religious subjects, including Heilige Carlo Borromeo and Heilige Claudius van Besançon, possess a calm, formal quality.

Modern collectors value Couvay for his technical skill and the historical weight of his subjects. His allegorical prints, like The Beautiful Abode of the Five Senses, offer a structured view of the world that fits well in contemporary interiors. These works act as windows into seventeenth-century thought. The monochrome palette of his engravings provides a sophisticated contrast to modern wall colours. His prints bring a sense of history and intellectual depth to a room without being visually overwhelming.