How the family left in the deceased's Gmail account access

If important information remains in the deceased's Gmail account and you want to access and retrieve it, what should be done with the remaining family members? People inside Google answer this question that will definitely occur in the near future (or has already happened).

Details to prepare for emergency situations are as follows.
Getting Access to Gmail Accounts of the Deceased

Death in the family - Problem-solving | Google Groups

1. Prepare and write out the full name and address of the representative in the family and the mail address that can be proved as the representative's name

2. Check the Gmail address of the deceased person, prepare and write it down

3. Copy the header of the mail sent from the deceased's Gmail address to the representative's email address, or copy the entire body of the email

4. Prepare death certificate of the deceased

5. Prepare power of attorney

6. If the family representative is the parents of the deceased and the deceased is 18 years of age or younger, prepare a birth certificate

It seems that it would be nice to send various documents in this way to the Google headquarters by fax or post.

What do you do in Japan? The procedure is the same, will I send it to Google in Japan?