I do something similar. Banks in Germany offer a so called HBCI/FinTS interface (I think it is mandatory for them). There are some open source libraries availab

I do something similar. Banks in Germany offer a so called HBCI/FinTS interface (I think it is mandatory for them). There are some open source libraries available to read transaction through this interface. I made a time triggered azure function to read all transactions from the bank for the day before and add them to YNAB via their REST API. Was a fun weekend projet... We then add categories manually to all transaction on the YNAB app, so... we go through each transaction every couple of days.