This paper updates the paper “On-Board Monitoring for EU7 challenges and possible approaches” (P. Goetschl and K. Klumaier, “On-Board Monitoring (OBM) for EU7—Challenges and possible approaches,” Baden-Baden, 2023.) presented at the 10th International Engine Congress in 2023. Although not all legal requirements and boundary conditions are final yet, development programs with SOP intent are already underway, supported by R&D programs to prepare for legal updates and future requirements. The precise measurement of legally regulated emissions onboard and the identification of emission critical combinations of multiple partially degraded system components are seen as major challenges. Two different approaches will be explained and compared to each other—from a technical point of view and from a time-to-market perspective. Our evaluation was done in the virtual environment along with selected measurements from ongoing development programs with a focus on LD (PC/LCV) applications. Specific HD requirements will be considered to ensure that our presented solution approaches remain universally applicable. First, the evolutionary approach is based on the traditional OBD set-up, reusing existing ECU functionalities, sensors, and empirical models. Additional logics are added that make a more extensive use of the existing ECU channels for plausibility checks on system level. The second approach, which is more revolutionary, introduces virtual emission sensors with physical models and an AI methodology (“MSA”) to enable an online detection of aged system components, even if partially degraded. With AVL’s expertise on virtualization and SW development, our OBM solutions were modified to better suit state-of-the-art ECU capabilities.