@Salve with a FP6 you can use the /e/OS/ regular camera App (fondation.e.camera) compatible with all /e/OS/ devices or the native Fairphone App (com.fps.camera) provided with FP6 Androïd stock.
This application may be better optimized for the FP6 hardware than the /e/OS regular one.
You can choose to enable /e/OS/ regular camera in Parameters \ Apps \ /e/OS Camera
However, as far as I know, the toggle to activate QR Code automatic recognition is only in the parameters of the native Fairphone camera App.