It'd be nice to be able to run some sort of statistic (e.g. Mann-Whithney) to determine group differences in bar plots when hue is provided. When significant (p<0.05) an asterisks can be added above those groups.

Nope, never adding this, sorry.
@ConstantinoSchillebeeckx Agreed, atleast if you have a column of significance stars, is there a way to add this to a bar chart?
@mwaskom Could you share your opinion on the question above? Using stars to show which result is significant is quite widespread practice, I'd like to show them if I have significance info as a column in dataset or any other format.
@iromeo and others: you may use https://github.com/webermarcolivier/statannot if you really need this, but I agree with @mwaskom that it should not be in seaborn.
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@iromeo and others: you may use https://github.com/webermarcolivier/statannot if you really need this, but I agree with @mwaskom that it should not be in seaborn.