A world talent can withdraw public pensions of Japan (National and Employee pensions) and get lump-sum refund. See more details in this page.
Some world talents subscribe also Defined Contribution (“DC”) pension (Corporate Type, iDeCo). At time of writing in Feb 2020, withdrawal criteria of DC pension are too stringent to be satisfied for most of cases. Therefore at present it may not be a good idea to subscribe a DC pension in case a world talent do not plan to stay in Japan for long, though DC pension subscriber can enjoy tax deductions. A world talent however automatically subscribes a corporate type DC pension if s/he works in a company which applies its DC pension to all of employees.
This restriction in withdrawal from DC pension is now seen as a problem and Social Security Council proposes improvement. So that in the near future, withdrawal from DC pension becomes more feasible through laws revisions. Please find more details in this page.