I don't think there is a standard process to do this. The reason for this i believe is not every employee need to have FND user.
I am sure you can achieve in many ways. One could to be use alerts
On PER_PERIODS_OF_SERVICE after an employee is terminated cancel all the scheduled requests by that employee if exists.
On FND_USER, if FND_USER is end dated (Those who are not employees) then cancel all the scheduled requests by that user if exists.
Thank you so much for the response. Yes. We do have a process but wanted to find out is there a seeded process that we could use.
no there is none
not supported but you can
update hold_flag or change phase_code status_code