The talented 20-year-old midfielder will travel to Spain to try to secure a professional contract and will leave Port Vila on 7 August, according to reports in his country.
Kalo was a star for Vanuatu at the u20 World Cup in Korea this year, where he scored three goals including two against Germany in a narrow 3-2 defeat.
His second goal against the European giants, a stunning free kick late in the game, catapulted him into stardom in his own country and his performances have earned him a trial at the Spanish club.
Kalo was given a pair of Nike football boots before leaving Vanuatu and he will travel with national team coach Moise Poida on the trip to Spain.
“This is going to be an intensive trial games that will mean displaying my very best performances, staying fit during those ten days, concentrating on every games, giving everything I have to the end of the trial. I believe in myself, the skills and disciplines I have acquired in international , after the Under-20 World Cup Tournament in Seoul 2017.
“I promise myself, my families, the Under-20 and all Football clubs and fans, the people and our leaders in Vanuatu that I will simply do my very best. I need both moral and prayer support from you all. I am not doing it for myself nor for pride but to show the world that Vanuatu has many young promising international football players out there.”
Leganes secured promotion to La Liga for the first time in 2015/16 and finished 17th last year, narrowly avoiding relegation.
They will face Real Madrid, Atletico Madrid and Barcelona as part of the Spanish league season this year.