This feat can be used in downtime, but takes the normal amount of downtime.
You're a creditor who has done business with many, many debtors. You can
Earn Income using
Intimidation as long as you're in a settlement or other area where your debtors have access to you. When you Earn Income using Intimidation, you spend no time gathering money; instead, it's delivered to you by a debtor at the end of the day, allowing you to simultaneously perform other downtime activities as long as you can still spend a few minutes every hour interacting with your debtors (such as Earning an Income by running a bar or Retraining at a gymnasium).