For now, a table visual can only form a separate excel file. The reason for this is that the data model of each table may have different filtering results (number of rows, column fields) due to its external conditions. The system is not able to integrate the table visuals into a single table by making a direct determination when exporting, and there is no function selection in the screenshot below.
You can manually put the data in the exported excel file into one file, hope it can help you.
Best Regards, Henry
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