When playing Armored Core VI: Fires of Rubicon with a compatible controller, vibrations are enabled by default. If you find the rumble to be too intense, then you can check out this tutorial to see how you can tone this feature down or turn it off completely.
1. For the first step, head into the System menu in Armored Core 6.
2. Inside of the System screen, select Game Settings on the left side.
3. On the right side of the same screen, you should see the Vibration Function slider. This will allow you to adjust the haptic feedback intensity of the controller.
4. By default, Vibration Function is set to 10. To lower it, you have to move the slider to the left. To completely disable it, move the slider all the way to the left side.
5. Once you are done adjusting the rumble intensity, exit the System menu.
When you start playing Armored Core VI: Fires of Rubicon again, you should notice a change to the vibration intensity of your controller.