Highlight selected Month

Hi feralvarez994 ,

As far as I know, Power BI doesn't support us to use cross-highlight in matrix visual. Matrix only supports cross-filter and None.

I suggest you to create an unrelated month name table to create the slicer.

Calendar =
ADDCOLUMNS (
    CALENDARAUTO (),
    "Year", YEAR ( [Date] ),
    "Month", MONTH ( [Date] ),
    "Month LongName", FORMAT ( [Date], "MMMM" ),
    "Month ShortName", FORMAT ( [Date], "MMM" )
)

Unrelated Month table =
SUMMARIZE (
    'Calendar',
    'Calendar'[Month],
    'Calendar'[Month LongName],
    'Calendar'[Month ShortName]
)

Relationship:

Then create a measure and use conditional formatting function to achieve your goal.

Color Measure = 
VAR _SELECTSHORTNAME = VALUES('Unrelated Month table'[Month ShortName])
RETURN
IF(MAX('Calendar'[Month ShortName]) IN _SELECTSHORTNAME,"Yellow")

Result is as below.

For reference: Use conditional formatting in tables

Best Regards,
Rico Zhou

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