Studying the linguistic repertoire of multilingual speakers is compelling and essential in today’s world. As travel abroad and linguistic community exchanges, whether physical or virtual, become constant features of life, understanding how speakers’ linguistic repertoires evolve and interact within their mind and speech is fundamental to understand the complexities of human communication. Although the phenomenon of multilingualism and language contact is widely observable, in fact, much of it remains unexplored: among the countless languages (and varieties of languages) and the even greater number of possible combinations between them, many aspects still await a detailed investigation.