Now more than ever before, there is a need for engineering solutions to global environmental problems. Towards this need, we see an increase in efforts towards incorporating sustainability into engineering education and particularly in engineering design education. Despite this work, there remains the need to investigate the influence of these interventions on students' individual differences, especially their trait empathy and attitudes towards sustainability. Such an investigation is important as these individual differences could influence students' ability to relate to sustainability-focused issues and act upon them. Consequently, our goal in this paper is to investigate this research gap by exploring the relationship between students' individual differences - specifically, their trait empathy and attitudes towards sustainability and their reflections on a sustainable design workshop in relation to a semester-long design project. Towards this goal, we conducted an exploratory study with 40 first-year engineering students from a large public university in the northeastern United States. The main findings from this study indicate the positive impact of participating in the sustainable design workshop on students' attitudes and intentions towards sustainability in addition to their perceived positive experiences with the workshop. These findings could inform future efforts towards devising pedagogical interventions that encourage a sustainability-focused mindset among engineering students, through engineering design education. [ABSTRACT FROM AUTHOR]