Hemineglect is a neurological condition in which individuals experience difficulty attending to stimuli on one side of their environment, typically due to brain trauma. This study aimed to develop a first mixed reality (MR) proof-of-concept (PoC) application for the rehabilitation of individuals with hemineglect, using the Design Thinking methodology. The proposed application involves an activity to practice visual scanning and to stimulate the lower limbs through interaction with virtual objects alternately generated on both sides of the individual. As MR devices do not natively support interaction via the lower limbs, we evaluated two methods for integrating this functionality: 1. MR device's controllers and 2. Third party trackers, both attached to the feet. Consequently, an in-depth comparison was conducted between the Meta Quest 3 controllers and the HTC VIVE Ultimate Trackers. In addition, for more accurate exercise evaluation and monitoring, a specific module was programmed to collect limb angle data using a digital goniometer via Bluetooth. This data source, combined with live visualization of the activity, provides healthcare professionals with a valuable tool for assessing the individual’s progress in the rehabilitation process. The MR application was presented to occupational therapists to assess its usefulness, usability, and therapeutic potential. Their feedback provided valuable insights for future improvements and iterations of the system.