This is one of the profiles in the Administrator (AD) open competitions, though in some cases Assistant (AST) exams may have an AST3 economist or economics-related profile announced for more technical positions.
Economists are required to have a relevant diploma, which is nevertheless not limited to studies in economics in a strict sense but any other subject that is closely associated with the tasks of an economist is also acceptable. The decision is always made by EPSO's Selection Board on the admissibility of the diploma.
See also:
EPSO | Selection Board | Administrator (AD) | Assistant (AST)
Related link: