Download user.cfg and copy the file to the folder containing the bf6 executable file.
GstRender.AmbientOcclusion 0
GstRender.ConsoleAntiAlias 0
GstRender.Enlighten 0
GstRender.LensDistortion 0
GstRender.ShadowQuality 0
GstRender.TransparentShadows 0
GstRender.WeaponDOF 0