One demand imposed by the global market is the possession of adequate soft skills, a challenge commonly faced by STEM (science, technology, engineering, and mathematics) graduates. This challenge is particularly prominent in China, which produces millions of STEM graduates annually. Consequently, there is a pressing need to develop and research programs facilitating the acquisition of soft skills, with a specific focus on teamwork, among Chinese engineers. To this end, we created a team-based project as part of a semester-long scientific English communication course at a Sino–foreign STEM university in China. The project aimed at fostering valuable soft skills through active learning, including teamwork, communication, and collaboration. In this report, we examine written reflections by students, aiming to assess their perceptions of soft skill development and overall experience resulting from their participation in the team-based project. Our results show the self-reflected soft skills development was considerable, and, unexpectedly, a noteworthy outcome of the project was the significant development of interpersonal connections, resulting in a positive experience and friendship development. Consequently, the findings of this study shed light on how teamwork can foster soft skills and friendship development, the latter often referred to as relationship development, another soft skill in the 21st century.