Dynamic date formatting based on user's browser language

Hi TSzreder , 

Because your yellow mark is the general date format, and red is the custom date, so when you change the language, only the language difference will be displayed, and the format is custom/fixed. If you want to achieve dynamic language, you can try to use slicer or set in power query：

Slicer way1:

1.Enter table as language slicer

2.Create a measure

Measure =
SWITCH (
    MAX ( 'Slicer'[language] ),
    "Polish", FORMAT ( MAX ( [Date] ), "dd/mm/yyyy" ),
    "US", FORMAT ( MAX ( [Date] ), "mm/d/yyyy" )
)

The final output is shown below:

Power query way2:

Best Regards,
Community Support Team_ Yalan Wu
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