It's no secret that companions can have different Gear or Outfits while tagging along to the adventure in Starfield. Some Outfits can be repetitive as they are found in multiple stores. On the other hand, there are a couple of Outfits that are one of a kind and available at one location, like the Swimsuit.
Starfield: How To Get Swimsuit
Acquiring a Swimsuit is a bit of a risky process in Starfield as players must perform an illegal action.