What is the best way to transfer domain mail from gmail to yandex?

Question

Google

There is a task to transfer domain mail from a gmail business account to yandex domain mail. What is the best and most convenient way to do this? If I disconnect the domain from my gmail account and connect the domain to yandex, then I will have access to my mailboxes and letters on gmail, so that I can pick it up using the pop3 mail collector on yandex, or will access to letters be lost when the domain is disconnected from gmail? Who has transfer experience? Share the algorithm of actions.
PS I made a backup of all data from google accounts, including mail in .mbox format, just in case, but as I understand it, it cannot be imported as it is on yandex.

Answer 1

I will answer myself. We make a backup using regular google tools:
https://takeout.google.com/settings/u/4/takeout , then install firefox thunderbird, connect it via imap to the account to which you want to import mail. Next, we import mail from .mbox into firefox thunderbird and synchronize it with the desired account.
The finish.

Answer 2

imapsync