I don't know about reversal, that would be an elegant solution.
Have you considered elongating or opening in the case and covering it with a bezel.
Order the next larger Nextion and sell the one you have. For me it is only the 3.5" unit (or larger I suppose) that fits my fingers. Have tried all sizes below 3.5". They work if I use a pencil to touch them but are very inaccurate with my fingers.