Marstrand's work is characterized by thorough research, drawing inspiration from sociology, philosophy and history of art, as well as visual artworks and popular culture. She brings a reflexive approach to photography, combining realism and fiction within a conceptual tradition of still life.
In 2023 she published her first photo book ‘Still Life of Teenagers’ with Danish publisher Disko Bay. The book explores the lives of Danish youth through photographs of their bedrooms.