Is there any way to reassign approval to a specific employee when enabling prohibit self-approval?

When we enable prohibit self-approval for an approval rule, we can also enable reassign the task to that employee's manager. If that is not checked the task goes to the next approver in the approval chain.

However, client does not use employee supervisor hierarchy for various reasons. In such a case, is there a way we can reassign the approval to another employee?