formating a matrix based on row and column headers

Hi tj41901,

You can set conditional formatting to apply the highlight color if the current row and column have the same values.

Measure =
VAR currRow =
    SELECTEDVALUE ( Table[Row] )
VAR currColumn =
    SELECTEDVALUE ( Table[Column] )
RETURN
    IF ( currRow = currColumn, "Red", "Black" )

Conditional table formatting in Power BI Desktop - Power BI | Microsoft Docs

Power BI Conditional Formatting for Matrix and Table Visuals (mssqltips.com)

Regards,

Xiaoxin Sheng