Select the icon (speech bubble) at the bottom or top of your screen.
If you prefer a physical copy, verify the region and subtitle support before buying. The Crown (2016) Svenska undertexter
If you own the series on physical media or a different platform and need to add subtitles manually, several databases host community-translated Swedish SRT files: Select the icon (speech bubble) at the bottom
: One of the largest repositories for Swedish SRT files for all six seasons. The Crown (2016) Svenska undertexter