Globally, Oliero (Oliero 
) is an extremely rare gender-neutral first name. Much more frequently, Oliero is the last name as well as the forename.
Marc, Jeremy, Julien, Vivien, Xavier, Morgane, Adeline, Aurelie, Charles, Bernard, Gwenola, Laurent, Florian, Lauriane, Hélène, Isabelle, Otacilio, Stephanie, Joseph, Goulwen, Denise, Robert, Carl, Jean, Manon, Serge, Lomig, Julie, Jules, Enora, Gwenaelle, Herve, Marthe, Michel, Muriel, Sandra, Sylvie, Alexis, Alicia, Andrew, Yoann, and Emmanuelle