The incident occurred in the St Pauli district of the city ahead of Poland and the Netherlands' afternoon match.
After the pandemic, the Ukraine war and the cost of living crisis, many youth shifted their support in the EU election.
It's unclear if she was hurt in the assault.
Social media footage showed a bearded man in glasses attacking people in the city's central Marktplatz square with a knife.
The fiery spectacle underlines the challenges faced by the island nation of almost 400,000 people.
The Vatican hasn't responded to requests for comment.
Concerns about misinformation, fake news and copyrighted material have intensified globally in recent months.
"The more such countries we have on our side, the more Russia will have to move."
A witness described the terrifying moment shots were heard.
