Sweden has negative rates when loaning in money, not when loaning out money. That is, they are not violating the zero lower bound - they are simply a bit closer to it.
The Swedish negative rates are for banks borrowing from the central bank, but in theory there is nothing stopping banks lending money to individuals at a negative interest rate. In a deflationary environment such loans will still have a positive real interest rate. The banks of course would only do so if the negative interest rate was less than what the central bank charged.
