Natural light-harvesting systems spatially organize densely packed dyes in different configurations to either transport excitons or convert them into charged photoproducts, with high efficiency. In contrast, artificial photosystems like organic solar cells and light-emitting diodes lack this fine structural control, limiting their efficiency. Thus, biomimetic multi-dye systems are needed to organize dyes with the sub-nanometer spatial control required to “sculpt” resulting photoproducts. Here, we synthesize 11 distinct perylene diimide (PDI) dimers integrated into DNA origami nanostructures and identify dimer architectures that offer discrete control over exciton transport versus charge separation. The large structural space and site tunability of origami uniquely provide controlled PDI dimer packing to form distinct excimer photoproducts that are sensitive to interdye configurations. In the future, this platform will enable large-scale programmed assembly of dyes mimicking natural systems to sculpt distinct photophysical products needed for a broad range of optoelectronic devices, including solar energy converters and quantum information processors.