User wants to know if there is a way to apply the fee schedule rates to an estimate, i.e., bill rates and cost rates already associated with activities.
In Core, fee schedules have resources (employees or vendors) and activities that are used to match bill and cost rates. However, estimates do not have resources and so there is no way to use the fee schedules rates on them.
On the other hand, budgets do have both resources and activities, which allows you to use fee schedules there. So you can either use budgets instead of estimates or create budgets and then convert them into estimates (by the click of a button).