You got me here to help fix the recording of your transactions in QuickBooks Online.
If you've categorized income as a transfer from the Banking page, you can still undo the categorization. This way, the transaction that was recorded as a transfer will be tracked as income.
To do that:
Go to the Banking on the left panel.
With the Banking page, select the Categorized section.
Locate the transaction that you'll want undo. It'll bring back into the For Review section.
Once done, we can categorize this transaction to your desired account. The steps below will guide you through the process:
Within the For Review tab, find the transaction you'll want to reclassify.