How do you transfer from Rakuten shoken to overseas investment broker without closing your position

I remember reading the post/comment but I can't find it.

For someone who did it or knows how to do it. How do you transfer your investment from Rakuten shoken to overseas broker such as Fidelity (US), etoro (Europe) without closing your positions when you plan to move out of Japan?

For example, say you have 65M total including unrealized gains in margin account in various investment products. Let's say I confirm that Fidelity/etoro sells all the financial products and derivatives I currently have in my positions. How do I do it?
I don't want to close my positions, just transfer them from Rakuten to overseas broker.

Edit:
More importantly can you transfer long dated derivatives?