reverse chart order in libre calc
# TO REVERSE X AXIS ORDER #
Right Click on your chart, go to Edit. The chart is editable now.
Then right click on the axis you want to change and go to "Format Axis".
Click on the Scale tab and check the box next to Reverse direction.
# TO MOVE Y AXIS FROM RIGHT TO LEFT #
Double click the the chart (to make it editable)
Then right click on it and select insert/delete axes..
under Axes: uncheck the Y axis
under secondary axes check Y axis