Hi there, @benjaminlbz.
I appreciate you reaching out to the Community. I can share information using API in QuickBooks Online (QBO).
I recommend that you sign up and post this question to our separate online forum called Intuit Developer Community. One of the experts handling Application Program Interface (API) will reach out and further assist you.
You may visit them through this link: Intuit Developer Support.
For more information about managing bank transactions in QBO, consider checking out this article: Categorize and match online bank transactions in QuickBooks Online.
Lastly, you may click this article to see information about reconciling your accounts so they always match your bank and credit card statements for future reference: Reconcile an account in QuickBooks Online.
Please know that I'm only a post away if you have more questions about bank transactions or anything else QuickBooks. I'll be happy to help. Take care always.