The new video - the second of a two-part report by state broadcaster IRIB - claimed she helped lead a training programme at Thomson Reuters directed "against the Islamic republic".
"Its aim was to train people to collect information on Iran under the cover of journalistic activities with direct financing from USAID (the United States Agency for International Development), which operates under the US State Department and the CIA," the voice-over in the video said.
The first video, shown on November 23, accused her of helping to launch the BBC's Persian-language service, which Iran sees as hostile to its Islamic regime, and helping to train its journalists.
The BBC has denied the claims, stating that she never worked for BBC Persian.
More From This Section
"She was employed as a projects assistant between February 2009 and October 2010 for the BBC's international development charity, BBC World Service Trust," it said in a statement.
"Ms Zaghari-Ratcliffe was never a journalism trainer but undertook administrative duties such as travel bookings, typing and filing," it added.
The videos have appeared just before she is due to face fresh charges in court of "spreading propaganda" on December 10.
Thomson Reuters chief executive Monique Villa said recently that the new charges risked a further 16-year prison sentence and were "a mockery of justice".
Zaghari-Ratcliffe was arrested at Tehran airport on April 3, 2016 after visiting family. She was travelling with her daughter Gabriella, now three years old.
The case has become highly politicised, especially after a "slip of the tongue" by British Foreign Secretary Boris Johnson last month in which he stated Zaghari-Ratcliffe had been training journalists in Iran, which has been used by the Iranian authorities to help justify the new charges.