After rumors of a standalone adventure called Ghost of Ikishima circulated late last week care of Xbox Era Podcast co-host Shpeshal_Nick, it seems that discussions about the title may further intensify as a domain for the title has been registered.
Ghost of Ikishima, or ghostofikishima.com, has been registered a few days ago and when visited, will lead to the PlayStation 4 games page. This could, of course, be either preparation by Sony when it is ready to announce the game, or simply an ruse by someone with a lot of time on their hands. Either way, it’s best to take this with a grain of salt.
For context, similar to Tsushima, Ikishima is actually the an island that is part of the Tsushima Strait that also suffered an attack from the Mongols back in 1274, making the connection a promising one for fans.
Ghost of Ikishima is rumored to be similar in nature to Miles Morales or Uncharted Lost Legacy, which is treated as a standalone release of a smaller scope.
Nothing has been announced by Sony or by Sucker Punch, so it would be best to wait for word from official channels, but there have also been talks and rumors about a post-E3 event from Sony where all of this could be announced.