Hi @sambhavbhandari -
Currently QS will not sort the Group/Color using a value. Here is a workaround that you can use.
Step 1 - Create a calculated field that will show your stacked group plus what rank the value is.
c_rank:
rank([value DESC],[col2], PRE_AGG)
Step 2 - Concat your rank + your stacked group.
c_sort_col1_string:
concat(tostring({c_rank}),col1)
Step 3 - Change the legend colors so that all stacked groups are the same color.
Step 4 - Hide the legend and create your own legend with a custom visual (if desired)
Result:
