Designated Beneficiaries for Interactive Broker account?

I am looking into Japan based investment accounts and if you can assign a designated beneficiary to the account. 

In the US – for example with one of the big mutual fund companies like Fidelity, they have a very straightforward way of assigning a designated beneficiary through their website.

I am wondering if a Japan based mutual fund / personal investing company like Interactive Brokers has a designated beneficiary system. 

I believe IdEco does. 

Regular Japanese banks do not.

As I get older I have come to realize that inheritance plans are super important.

Has anyone successfully added a designated beneficiary to an IB account?

by Loveyourweenus