For migration between G suite and Office 365 you can use FixVare IMAP to IMAP Migration Software. This tool allows you to migrate data between any services that support IMAP. To use this tool, you only need the IMAP credentials for each account, and then it will start the migration after syncing them. It offers bulk migration and deep filtering, allowing you to easily perform selective email transmission. This tool functions on each windows version. It will preserve the email attachments, their attributes, and other details, allowing you to transmit the emails safely and correctly.