Data label value shows as percentage is not supported in Excel.
In Excel, number format can be applied on the data value.
So from conversion from ods to xlsx, if value is set as "value as percent", percentage number format will be set for that value. Value wont be converted to percentage.
for example, if in ods file, value "11232" is set as "show value as percent", it will be displayed as 35%
The same is not supported by excel.
Only number format can be set in excel(i.e 11232%)
The same doesn't retain in internal conversion(i.e ods-xls-xlsx)