Previous studies have proposed a communication enhancement system with haptic feedback using a smartwatch to present nodding responses. The effectiveness of this system has been examined in daily life scenarios. In this study, we evaluated the communication effects of the system during first-time conversations through two types of experiments: one comparing different vibration patterns and another comparing the presence or absence of vibration feedback. The results indicated that the optimal vibration pattern varied among users, suggesting individual preferences even in first-time conversations. Additionally, the evaluation of vibration presence showed that the system effectively supported communication for users. Moreover, listeners who engaged in conversations with system users demonstrated a deeper understanding of their conversation partners when vibration feedback was present. These results confirm the communication effects of smartwatch-based haptic feedback in facilitating smoother communication in first-time interactions.