Hello there, @Philipt.
You can create cleaning accounts that will serve as a Factoring Company in QuickBooks.
Once, done, you can now move money from one account to another account using the clearing account.
Also, if you need some references in the future, you can always access our site: Help articles for QuickBooks Online.
Please let me know in the comment section below if you have any other questions. It'll be always my pleasure to lend a hand.