There. The first, ultra-long chapter. I hope NedCan is okay. I first had England as Canada and America as Netherlands, but then I thought that'd be very awkward for America. xD

I made a list! Look!
Character; in whose body they are
America; Canada
Australia; Switzerland
Austria; England
Belarus; Germany
Belgium; Hungary
Canada; Belgium
China; Belarus
Denmark; Seychelles
England; Netherlands
Finland; France
France; Ukraine
Germany; Japan
Greece; Finland
Hungary; America
Iceland; Turkey
Japan; China
Lithuania; Sealand
Netherlands; Spain
Norway; Greece
Poland; Sweden
Prussia; Austria
Romano; Prussia
Russia; Veneziano
Sealand; Russia
Seborga; Iceland
Seychelles; Australia
South Korea; Denmark
Spain; South Korea
Sweden; Lithuania
Switzerland; Seborga
Turkey; Norway
Ukraine; Poland
Veneziano; Romano