Do transaction controls work for project budget/forecast entry

Summary:

Client has transaction controls at task level, which allow only certain expenditure types to be used on actual project transactions. They want to extend the transaction controls functionality for project budget entry and project forecast entry. So the user can only select or use the expenditure types (or expenditure types belonging to the selected expenditure category) at budget entry/forecast entry. What are the options to achieve this feature?

Note we are not using budgetary control functionality.

Content (please ensure you mask any confidential information):

Client has transaction controls at task level, which allow only certain expenditure types to be used on actual project transactions. They want to extend the transaction controls functionality for project budget entry and project forecast entry. So the user can only select or use the expenditure types (or expenditure types belonging to the selected expenditure category) at budget entry/forecast entry. What are the options to achieve this feature?