Support for ESP32-S3 PowerFeather on PlatformIO has just been merged:
https://github.com/platformio/platform-espressif32/pull/1344
However, it might take a while until the next stable release when the board is selectable when creating a new project in the Project Wizard.
In the meantime, you can use the development version. You can do so by creating a new project with a different ESP32-S3 board, and just editing the platformio.ini afterwards to something like:
[env:esp32s3_powerfeather]
platform = https://github.com/platformio/platform-espressif32.git
board = esp32s3_powerfeather
framework = arduino ;or espidf
