Edit - beach theme is still free.
Free theme as part of “The last of us day” aka “outbreak day”.
According to the pair, all existing themes and avatars for The Last of Us Part II are 100 percent free, no strings attached, via the PlayStation Store until September 28 at 11:59 pm PT. Included in this is a brand new theme.
The highlight of this is possibly The Last of Us Part II Beach Theme, a dynamic theme based on the game that comes with custom music, custom icons, and custom sounds. And unlike most of the game, it doesn't make you actively distressed and depressed.