Can I play Fortnite with a controller on cloud-streaming services?

Yes, you can play Fortnite with compatible controllers depending on which cloud-streaming service you are using. See below:

• Xbox Cloud Gaming: Check out Xbox’s support (Opens in a new tab) website for the list of supported controllers. On smartphones and tablets mobile devices specifically, players can use either a controller or touch controls.
   

• GeForce NOW: The list of supported controllers varies depending on the device you’re playing on. See the GeForce NOW system requirements (Opens in a new tab) page to see the supported controllers per device. All devices support the Sony DualShock 4 (PS4) controller, Sony DualSense (PS5) controller, and Microsoft Xbox Wireless controllers.
  For game streaming on mobile devices specifically, players can use either a controller or touch controls.
   

• Amazon Luna: See the Amazon Luna Getting Started (Opens in a new tab) page to see the supported controllers per device. All devices support the Luna Controller, the Sony DualShock 4 (PS4) controller, and Xbox One controller. Using the Luna controller app, players can use their mobile device as a controller for all Luna-supported devices, even other mobile devices!
  For game streaming on mobile devices specifically, players can use either a controller or touch controls.