Not necessarily. Today's generative AIs are multilingual and can process and cite content in Portuguese without any trouble. If your audience is Brazilian, create content in Portuguese. If you serve international markets, then yes, it makes sense to have English and possibly Spanish versions.
What matters more than the language is the quality and structure of the content. An excellent article in Portuguese will be cited by AIs when someone asks questions in Portuguese. The barrier is not linguistic, it is about authority: if your domain has few backlinks and little presence in reference sources, it will be ignored regardless of the language.
That said, if your segment has little coverage in Portuguese, you have an opportunity. AIs need Portuguese-language sources to answer questions in Portuguese. Being the first to create quality content on a topic in the local language can lock in a reference position for a long time.