Problem:
- As a Project Manager, I need to be able to calculate the time spent on a task * external rate, in order to understand the total cost of a specific task or groups of tasks.
- The goal is then to sum all tasks cost to understand the overall cost of the project in a client implementation.
This being said, is it possible to create a formula that calculates an external rate and the time spent to be available in the list view main fields?

Is this doable by personalized custom fields? If so are this kind of fields available on Jira Work Management?
Thank you.