Research on translanguaging in science and engineering education has grown rapidly. Studies carried out across diverse contexts converge in their commitment to fostering equity in science and engineering learning for linguistically marginalized learners. However, the rapid growth of this research area has exposed different approaches to conceptualizing "equity" itself. The purpose of this review of literature was to examine what equity approaches have undergirded research on translanguaging in US K-12 science and engineering education and whether these approaches vary over time and across contexts. We systematically analyzed studies (N = 15) using the four equity approaches articulated in a recent report by the National Academies of Sciences, Engineering, and Medicine (2022). Findings of our review indicate that, while studies aimed at increasing opportunity and access to high-quality science and engineering learning (Approach 1) and, to a lesser extent, identification and representation with science and engineering (Approach 2) were the two most prevalent equity approaches, studies focused on expanding what constitutes science and engineering (Approach 3) and seeing science and engineering as part of justice movements (Approach 4) were somewhat less common. Furthermore, justice-oriented approaches to equity (Approaches 3 and 4) were increasingly visible in the literature since 2020 as well as in research carried out in nontraditional educational contexts (e.g., out-of-school programs, classes outside of the core school subjects). Based on these findings, we propose the need for future research that (a) explicitly conceptualizes and operationalizes constructs related to equity (e.g., what is meant by "achievement" and how it is measured), (b) examines the possibilities and tensions associated with expanding what constitutes science and engineering in traditional educational contexts, (c) leverages the affordances of multiple STEM subjects for addressing justice issues impacting linguistically marginalized communities, and (d) iterates on the equity approaches themselves.