Alexandria is primarily known as the See of St Mark. But in the fifth century Pope Leo of Rome, in responding to the increasing claims of Constantinople, underscored the idea of "Apostolic" sees, and claimed that Rome, Alexandria, and Antioch were not only "Apostolic" but "Petrine". This is clear with regard to Rome and Antioch (both associated with SS Peter and Paul, though St Paul doesn't get much more than honourable mention for some reason), while with regard to Alexandria, the Petrine claim is through St Mark, as the disciple/secretary of St Peter. This focus on apostolicity (and even the Petrine focus) was to counter the idea that, with the moving of the imperial capital from Rome to Constantinople, the latter should enjoy prerogatives above Alexandria and Antioch, and certainly at least as equal to Rome.
I don't know if there are any "Sees of St Paul". The only ones I know of that are linked to St Paul are also linked to St Peter. But I don't know if anyone out there claims to be the Successor of St Paul. Maybe he was too itinerant an apostle to settle down somewhere long enough to "establish" a see.