As per Directorate of Central Health Establishment of Pakistan, Polio Vaccination Certificate is required for Pakistani travelers departing from Pakistan. The vaccination certificate is valid for one year from the date of issue. Also as per prevailing conditions COVID PCR test is also required.
http://www.doche.gov.pk/Detail/NjMyMzdjMjgtNjg4My00OTZkLTg3YWUtMDc0NTUwNjIyMGEw