Hello,
How are you doing. This project looks interesting and I think I can help you achieve what you want. I have experience mving data from and to various database structures, including PostgreSQL, MySQL, Microsoft SQL, MongoDB and redis. As a matter of fact, my own startup uses a mix of these and I could provide you with migration scripts so you get both the migration and a work base for any subsequent migration need. I hope we can talk about the project, I can be reached by any mean, phone, skype, whatsapp, viber, etc.