Sorting stacked chart

It is possible but, only in a static way.
It means if you have a slicer for the period for example the sorting order will be the same as for all periods.

If it's good enough you can apply these steps in PQ :
1. Duplicate the table

2. Group new table by category, summarizing the value  :

3. Sort the table by sum of values in the descending order 

4. Add index column :

5. Add a conditional column with some unreal big value for others :

6. Remove unneeded columns + modify data type of sort column to the whole number and close and apply

7. create a relationship with the original table :

8. sort category by sort column from table view :

9. Drag the data to the Graph with the legend from the sorting table and , modify the sorting from the graph 

The modified pbix is attached.

PS

Sorry I didn't understand right away what you meant to do; the scary stacked chart took up most of my brain power. 🙂 I strongly recommend, though, to share with whoever is requesting you to make it the difficulties in interpreting it, both as a user and as a data visualization expert.

If this post helps, then please consider Accepting it as the solution to help the other members find it more quickly