Alisha's Westlake and North Harbour teams defeated Malia's St. Cuthbert's and Marist sides in multiple close encounters.
"She knows how I shoot so maybe that's why they won," Josephson laughed.
The duo from Mount Maunganui will pair up again for the young Kiwi team at the world champs in Auckland, with their first game set to be against South Africa at the AUT Millennium National Aquatic Centre on Monday night.
"It's good coming back together to play after what feels like a long time, especially for New Zealand," Josephson said.
The pair are part of an ever-growing group of water polo talent coming out of Mount Maunganui College, including Rio 2016 Olympian Joe Kayes, who played for Australia, and Rebecca Parkes who is lining up a Tokyo 2020 spot for Hungary.
Earlier this year, Mount students Bae Fountain and Justin Pickering represented New Zealand at the FINA World Men's Youth Water Polo Championships in Montenegro.
Senior women's coach, Angie Winstanley-Smith, has been helping to coach the NZ youth squad leading up to the international championships and she's excited about the potential result.
"They are a strong team with every position well covered. I think our team might be underestimated and the girls will definitely pull something out of the bag."
The New Zealand women's youth squad has hopes of competing at the 2020 Summer Olympics in Japan. The team has been training this week against Canada, Italy, and the Netherlands in preparation for their first game.