Accelerating a train rapidly throws the driver back into the seat, but the HUD accelerometer moves up (forwards). I find that confusing. Will (or is) there any option that can invert the HUD display?
I have not seen any display or gauge in real life that would show acceleration/speed by going left or downward
Correct me if I'm wrong, but I remember that it was showing G-force back in around TS 2012-15. The little white dot in a rainbow-radial-gradient square.
That is Train Simulator Classic, and it has a g-force meter in Career mode on the left hand side (because you get deductions for hard driving and annoying your passengers if the scenario author decides to use the feature). You are referring to an accelerometer though in your thread title, which is always positive up or right, negative left or down. So it's correct and intuitive in TSW.