Either 8 or 9 depending on how you count.
Antigua & Barbuda - St. John’s
Canada - Ottawa
Italy - Rome
Mexico - Mexico City
Saint Lucia - Castries
Scotland - Edinburgh (almost a country?)
United Kingdom - London
United Arab Emirates - Abu Dhabi (most recent)
Vatican City - Vatican City (knock on wood)
And get to add Tokyo by the end of this year!
In terms of countries, I sadly have not seen the capitals of Morocco, the USA, Germany, France and the Netherlands yet.