Shoviv Gmail backup Tool 

You probably have the MBOX File if you back up your Gmail account with the Takeout services. This data file contains all messages and other attributes. There are two options to import MBOX files into your Gmail account:

#1 Solution: Import MBOX to Thunderbird, configure Gmail and manually drag and drop the files to Gmail.

#2 Solution: Shoviv Gmail Backup Tool allows you to import MBOX files directly into your Gmail or Google Workspace account.

For other Imap clients: Shoviv IMAP Backup Tool

Official website: https://www.shoviv.com