If you're looking for HubSpot Service Hub migration, be sure to check Help Desk Migration. You can use it to migrate the following records:
- tickets with related details - contacts - organizations - agents - custom fields
After the migration, you can download the reports with migration results to check if all records are there. The report provides explanation, if there are some errors.
You should check alternative tools like Help Desk Migration to move your data automatedly. This one supports CSV import and export and offers customization options. You can read more about it here: https://help-desk-migration.com/how-it-works/