Почитал информацию про ограничения на въезд на оф сайте ЕВРО
https://www.uefa.com/uefaeuro-2020/event-guide/budapest/plan-your-trip/need-to-know/, нашёл такую информацию:
"Hungary, Azerbaijan and Russia have put special procedures in place:
As a ticket
holder travelling to Budapest, you won't be required to quarantine. Other entry requirements such as a negative COVID-19 test result still apply.
International travel to Baku is not permitted for non-residents at all, however ticket holders who are citizens and/or residents of Turkey, Switzerland and the UK plus quarter-finalist countries will be able to obtain a visa. They will be eligible for a quarantine exemption, with proof of a negative COVID-19 test result.
Exemptions for Saint Petersburg ticket holders are also being developed.
In addition,
if you're going to Bucharest you may be able to benefit from the quarantine exemption if you can present a negative COVID-19 test result and limit your
stay to less than three days."
Ни слова про повторное тестирование по приезду в Будапешт и ограничение пребывания в теч. 3 суток.
Может для ЕВРО, действительно, небольшие смягчения на въезд для болельщиков прорабатывают :)