Swedish citizens do not need a Visa for visits to Hong Kong or Macau. You may stay up to 90 days as a visitor.
The Swedish passport does however require an expiration date at least one month longer than the planned visit to Hong Kong or Macau. For example, a stay in Hong Kong for two weeks would require an eligible passport for at least six weeks.
If you are planning to study or work during your stay in Hong Kong or Macau, you need of a Visa.