This paper extends prior blended-care research on a chess training application originally developed for older adults. It explores how this app can be adapted for individuals with cognitive disabilities as well as those who are blind or visually impaired. By using a participatory design approach, end-users were actively involved in customizing the app’s accessibility features, interface design, and training content. Our findings suggest that inclusive and accessible serious games can lead to improvements in both cognitive and social outcomes, highlighting the importance of iterative, user-centered engagement. We also demonstrate how the Web Content Accessibility Guidelines (WCAG) 2.1 can be translated into practical solutions in e-health. Future work will further validate these findings with larger sample sizes to refine and confirm the app’s benefits for diverse populations.