Shine was 15 when she was part of the under-17 squad who lost the final of the 2010 UEFA Women's Under-17 Championship in Switzerland. She then participated in Ireland's 2010 FIFA U-17 Women's World Cup campaign. At the 2014 UEFA Women's Under-19 Championship, Shine scored the only goal against Spain as Ireland won their group, before crashing 4–0 to the Netherlands in the semi-final. She had recovered from a broken leg sustained 10 weeks earlier.