you are making a mistake here as most of the people with unfamiliarity of the subject. A priori, you are not considered tax resident of the country you have second citizenship ONLY if you hold some mickey mouse CBI passport. This is a requirement put by US and EU so the carribean states can continue selling documents and EU and US to squeez you financially. BUT in all other countries which you gain citizenship by naturalization you are automatically considered resident and tax resident of the country. How this is possible: because naturalization means living permanent in one place and having all your financial activity there and then for this by time you gain citizenship rights. Trust me , I know what I am writing, one can have three different citizenships and three different tax residencies. each country considers you only their citizen!