In addition to her continuing research and publications in the field, Sousa teaches a number of related courses in Latin American history, Mesoamerican literature and gender studies, and also provides instruction in learning Nahuatl.
[6] During the course of her studies at UCLA Sousa obtained a proficiency in Classical Nahuatl, an indigenous language of the central Mexican altiplano and lingua franca of the Aztec Empire at the time of the Spanish conquest in the 16th century.
[4] In 1998 as her PhD was being completed, Sousa co-edited and translated an English-language edition of the Huei tlamahuiçoltica, a 17th-century Nahuatl-language manuscript that is central to the claims of the Guadalupan apparition to Juan Diego.
Together with her collaborators Stafford Poole and James Lockhart, Sousa affirms that Luis Laso de la Vega was indeed the principal author of the Huei tlamahuiçoltica,[7] and that portions of the work bear affinities with Sánchez's document.
[11] In 2005 Sousa co-edited with Matthew Restall and Terraciano a volume of translated colonial-era Nahuatl-, Mayan- and Mixtec-language primary source texts, under the title Mesoamerican Voices: Native-Language Writings from Colonial Mexico and Guatemala.
The book is a social and cultural history of gender relations among indigenous peoples of New Spain, focusing on four native groups in highland Mexico―the Nahua, Mixtec, Zapotec, and Mixe―tracing cross-cultural similarities and differences in the roles and status attributed to women in prehispanic and colonial Mesoamerica.