Where to use which one…
The one that comes under Excel tab must be put inside Excel application scope . And this allow you to to perform multiple operation (Read Cell/Write Cell/,Write Range/Read Range,/Read Cell Formula)on a current excel rather than opening multiple operation activity on multiple excel.
Where as for Workbook Tab you don’t need to use Excel application scope .
Here each activity (Read Cell/Write Cell/,Write Range/Read Range/,Read Cell Formula) have file path property.
Beside all the property are identical.
Note also than the App integration activities requires having the excel application installed on the machine where the Workbook activity do not.