matrix visual with nested rows and columns

Hi powerbiexpert22 

Maybe you can try to use the stepped layout:

You can easily adjust the stepped layout settings. With the matrix visual selected, in the Format section (the paintbrush icon) of the Visualizations pane, expand the row headers section. You have two options: the Stepped layout toggle (which turns it on or off), and the Stepped layout indentation (which specifies the indentation amount, in pixels).
Here is the link for your reference:

Stepped layout with matrix visuals

Best Regards

Zhengdong Xu
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