Hello, one suggestion would be do so.
- Open the Epic Games Launcher.
- In the top-right corner, click on the initial of your Display Name
- Select Settings.
- Scroll down and expand Fortnite.
- Check the box for Additional Command Line Arguments.
- Type: -d3d11
- Relaunch Fortnite.
If you want it to be directx12 you will need to delete -d3d11 and uncheck that box.