Hi @Anonymous ,
As @efialttes said, if you want to update a "Yes/No" column in a sharepoint list, you could update the Yes/No type column with true or false, you could take a try to update the column with custom value from the if() expression provided by @efialttes .
And you could save the column value from the excel row in a Compose field, then you could use the if expression to check if the value is equal to yes, if the value is equal to Yes, update the Yes/No column in the list item with true, or if the value is No, update the Yes/No column in the list item with false.

Best Regards,
Alice
Community Support Team _ Alice Zhang
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