This is still possible without a Workdate function - it’s a matter of using If and Weekday() to determine which day of the week we are on and then adding the appropriate number of days. The example below adds two workdays to an entered date, for example:

IF(WEEKDAY({Date 1}) > 3, DATEADD({Date 1}, 4, ‘days’),IF(WEEKDAY({Date 1}) = 0, DATEADD({Date 1}, 3, ‘days’),DATEADD({Date 1}, 2, ‘days’)))

Note - WEEKDAY returns a 0 for Sunday up to a 6 on Saturday. So, this formula adds 4 days for a start date on Thursday, Friday or Saturday, 3 Days on a Sunday and 2 days on Monday, Tuesday or Wednesday.

Note this returns an American date format an if you want something else you can apply the formatting described above.

Hope this helps.

Julian