Which of these comes closest to your situation?
Portugal — Exceptional Talent
Portugal has no general talent visa. There is one discretionary citizenship route for services rendered to the Portuguese State, and a set of employment routes that work well for distinguished applicants — each of which depends on a Portuguese institution wanting you rather than on your record in the abstract.
I have rendered, or been asked to render, services to the Portuguese State → I'm recognised in my field — awards, publications, senior standing — but have no Portuguese connection → I have a job offer in Portugal in a senior or highly qualified role → I'm a researcher and a Portuguese institution would host me → I've been invited to work on a cultural project in Portugal → I'm not sure which of these fits me →