It is currently not possible. 

On the screen of daily data , monthly data , yearly data, etc., for example, the total of 3 hours is displayed separated by dots such as 3.00. It's currently not possible to have a colon-separated view like 3:00.

This is because ":" is a symbol for time notation, such as "hh:mm", and is generally not used for aggregated time.

About output data (export)

In the monthly data output and daily data output, the time delimiter can be ": (colon)".

From Export/Import Output Data (Export) , open [Monthly Data] or [Daily Data]. Select "Target year/month", "Output layout", "Target division", "Target employee type" and click the [output data] button.

You can select ". (dot)" and ": (colon)" in the "Time separator" item on the next screen.

Caution
When the time separator is changed to ": (colon)", the number of seconds is also exported. Please note that it is not possible to export the number of seconds as ": (colon)".