However, there are a couple easy workarounds.
One option is to copy an entire worksheet into another workbook.
In a second open workbook, there are no custom table styles.
Then check “create a copy”.
When I click OK, a copy of the sheet is moved into the other workbook.
At this point, the custom style has been imported.
As you could see in the Table Styles menu.
Then I can apply the custom style.
Another way to copy in a custom style is just to copy and paste the entire table.
I’ll first delete the custom style.
you could see it’s now gone from the workbook.
Now I’ll pick the original table.
The trick here is to opt for entire table, including headers.
To do this, you could hover over the upper left corner until you see the diagonal arrow.
Or, you select any cell in the table, and use the shortcut Control + A twice.
Now I can just copy to the clipboard, and paste the table into the original workbook.
Again, the style is automatically imported.
I can now delete the pasted table and apply the custom style.