Lots of people have, and the manufacturer included the diagram to make sure that people understand the coordinate system. It does not matter that the manufacturer's chosen axis labeling does not define a right handed system, as you are free to relabel an axis or invert the sign of the data in any way you like. The simplest fix is invert the sign of the data from any ONE of the three axes.
Gravity is measured as a positive acceleration along any axis that is pointing up, due to the upward force exerted by whatever is preventing the sensor from falling. That is consistent with the direction for all other positive accelerations.
Hi, thanks for your prompt reply. Unfortunately, the top-left corner is pin 1 in the top view. But it makes sense now. Only a negative sign should be added to the program to make it same to the data sheet.