Using text files. The expenses can be tracked with beancount. It tracks many in or out of many bank accounts with the "double-entry accounting".
Documents can be attached to transactions, etc...

The dataflow is the following:

1. Download transactions from the bank (csv, pdf or ofx files).
2. Convert these files to the beancount format. There are many plugins available.
3. Balance the transactions to get the "double-entry accounting"

In my experience so far, it has been the exact opposite. The entire process has never taken me more than 45 minutes to finish. Considering that I do this once a month, the time investment seems more than fair. And the added benefit is that by balancing these transactions by hand, I get a fairly good idea of what was happening in my accounts in the previous month.

Visualization can be made with SQL queries, or Fava as UI. See a demo