How do we customize the pivot chart column headers based on value selected in slicer in power bi?

Hi ShaibazA1 ,
It is not supported to change measure names dynamically because Power BI uses a definite name to refer to a measure. 
But you can refer to this post :-
https://community.fabric.microsoft.com/t5/Desktop/Matrix-column-names-based-on-slicer-selection/m-p/1959408#M743441
Hope this was helpful.
Thanks ,
Pratyasha Samal
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ShaibazA1 ,

Please refer to this thread for the technique.

Solved: Re: Matrix with Dynamic Column Heading - Microsoft Fabric Community

However, please note that depending on your desired outcome / data structure, this technique may not be usable.

Hi ShaibazA1 ,

You can submit the idea here. Users with similar needs can vote for the idea when searching the site, and when there are enough votes, the product team will consider adding it to a future release.🤗

Best Regards,
Gao
Community Support Team

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If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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