Socialstyrelsen is the institution that deals with Nursing convalidations in Sweden.
Home page: http: http://www.socialstyrelsen.se
For qualified EU nurses:
http://www.socialstyrelsen.se/applicationforswedishlicencetopractiseeea/nurseresponsibleforgeneralcare
For nurses qualified outside the EU:
http://legitimation.socialstyrelsen.se/en/educated-outside-eu-or-eea/nurse-responsible-for-general-care