Marta is a six-time FIFA women's player of the year but has never won the World Cup, playing in the Brazil team that lost 2-0 to Germany in the 2007 final in China.
"I'm counting on her, I'm counting on all the players who are in form, like Marta," Elias told AFP on Sunday.
"But neither she nor I know whether she will take part, only time will tell."
Last May, Marta was called up to the Brazil squad for the first time in nine months.
She had said following Brazil's Olympic final defeat to the United States in August 2024 that she had probably played her last match for her country.
But back in the squad, she was then selected for the women's Copa America in July 2025, winning that for the fourth time in her career.
She subsequently revealed that she was not ruling out playing on for the Selecao until the 2027 World Cup.
Her 17 goals in the tournament is a record.
Whoever he picks, Elias believes that Brazil, whose men's team have been world champions a record five times, have a great chance of finally winning a first women's title.
Brazil will become in 2027 the first South American nation to host the Women's World Cup.
"We have a great opportunity because the Selecao is going through a great moment and we have young players who will keep improving between now and the World Cup," he said.
"It will be difficult, but playing at home increases our chances. I'm feeling optimistic."