Once a manager arrives on the compensation landing page, what controls the number of plans...

The Compensation Manager is responsible for granting access to the plans, and the Line Manager will only have access to the plans that they have been granted access to. Other factorssuch as all active plans for the current year, plans that the Line Manager has employees eligible for, or whether the manager is eligible for the plan, will not affect the number of plans that the manager has access to allocate compensation.

https://docs.oracle.com/en/cloud/saas/human-resources/23a/faiwc/how-you-add-dashboard-otbi-reports-to-the-workforce-compensation-landing-page.html