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".

The Markit/CIPS manufacturing Purchasing Managers' Index grew to 50.1 from 49.4 in April, which had been the lowest reading since early 2013.
The 50 mark separates manufacturing growth from contraction, with the sector now just on the positive side.
Manufacturing failed to boost overall UK growth during 2015 and early 2016.
UK economic growth slowed to 0.4% in the first quarter of the year from 0.6% in late 2015, propped up by the services sector.
Rob Dobson, senior economist at survey compilers Markit, said: "The manufacturing sector looks likely to act as an increased drag on the economy in the second quarter.
"There are also signs that increased client uncertainty resulting from slower growth and the forthcoming EU referendum are weighing on investment spending and business decision-making in general."
The report found that more than a third of manufacturers surveyed believed uncertainty over the EU vote has had an impact on their business, with 8% saying the effect was "strongly detrimental".
The survey showed the investment goods industry experienced a difficult month, with production falling at the quickest pace since early 2013.
Howard Archer, chief UK and European economist at IHS Global Insight, said the manufacturing sector was "essentially at a standstill in May".
Ruth Miller, UK economist at Capital Economics, said the small improvement for manufacturing in May did little to change the fundamental picture of a struggling industrial sector.
"Granted, the headline PMI index recovered from its three-year low in April, ticking up from an upwardly revised 49.4 to 50.1 in May, above the consensus expectation of 49.6," she said.
Ms Miller said this was still far below the average since the economic recovery picked up at the start of 2013. However, she thought the situation would "improve for UK manufacturers later this year".
Overall new orders rose in May.
Meanwhile, some firms said they were already pricing in the expectation that inflation will rise. Annual consumer price inflation currently stands at 0.3%.

The poverty rate was 15% in 2011, meaning 46.2 million Americans were in poverty, staying flat after three previous years of increases.
Real median income of households in the country dropped by 1.5%.
The average poverty threshold for a family of four in 2011 was $23,021 (Â£14,300).
Income inequality, as measured by the Gini index, increased by 1.6% in 2011, the first time there has been an annual rise in the index since 1993.
The percentage of Americans lacking health insurance fell to 15.7% from 16.3%, the report also said.
Poverty in the US reached a record high in 2010, at 15.1%.
England Under-19 Women's and Fylde Ladies midfielder Zoe Tynan has died, aged 18.
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UK manufacturing activity rose slightly in May, raising concerns over the economy's strength in the run-up to the 23 June European Union referendum.
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The percentage of Americans living in poverty is statistically unchanged from 2010's record high, even as household income fell, a US Census report says.