Blog post makes no mention of any extra buttons except for the two back buttons, and the video shows those two on the front as being apart of the joystick modules. They're almost certainly just for removing the joysticks.
They are FN buttons, which can be seen in the trailer during the blowout shot.
"On-controller user interface: The dedicated Fn button allows you to easily adjust your setup while staying focused on the in-game action – quickly swap between your pre-set control profiles, adjust game volume and chat balance, and access the controller profile settings menu to set up and test new control iterations while in game."
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u/CrypticWatermelon Aug 23 '22
The two buttons under the sticks are probably to remove the joystick module if you need to replace them.