Tynan, a former Manchester City player, died after being hit by a train at West Allerton station in Merseyside on Tuesday, British Transport Police said.
Tynan's death is not being treated as suspicious.
Her family paid tribute to a "vibrant, generous and fun-loving girl", who was "a dedicated athlete, never happier than when she had a ball at her feet".
Tynan began her career at Liverpool Feds, spent six years at Everton's Centre of Excellence and was playing for Women's Premier League side Fylde Ladies.
A family statement also said she was a "the most loving and caring daughter and sister anyone could wish for" and that she was the "ultimate team player".
It added: "Zoe always knew how to cheer anyone up, and was a loyal, straight-talking friend to many. She touched so many people's lives and will never be forgotten."
Tynan joined Manchester City in 2015, making one Women's FA Cup appearance before moving to Fylde.
Floral tributes have been left at the scene, according to the Liverpool Echo.
England internationals including Lucy Bronze and Casey Stoney have also paid tribute.
Fylde manager Luke Swindlehurst said: "We want to remember Zoe in the best possible way: a hugely talented player and an immensely likable character."
Tynan had appeared for England at various youth levels and was recently included in the Under-19 squad for a training camp at St George's Park.
The Football Association said it was "deeply saddened" by the death and Tynan's Under-19 coach Mo Marley described her as a "hugely-liked and popular member of the team".
England Under-19 Women's and Fylde Ladies midfielder Zoe Tynan has died, aged 18.