I would suggest converting the Access database to a sql server database. Microsoft offers a pretty straight forward tool to do this. From there you can use the database connector.
If you end up going the excel sheet route. Check out this article to make it a little less tedious.
https://docs.mendix.com/howtogeneral/tips/import-a-large-excel-file
As a workaround you could try to transfer all the data from Access to Excel first and then just import the different Excel sheets.
Regards,
Ronald
Ya. That was my first thought as well. I was hoping that someone may have come up with something less time consuming. haha