Hello there,
Recording an asset depreciation in QuickBooks Online should be manually tracked using journal entries. I'm here to provide you the steps on how you can record this.
Before proceeding, please know that calculating an asset depreciation is best done with an accountant. We recommend working with them to regularly review how you track depreciation. Let's start with checking if you already have a depreciation account:
- Go to the Gear icon and select Chart of Accounts.
- In the Filter by name or number field, enter Depreciation.
- Choose the Depreciation account if you already have one. If you see none, create a Depreciation account under the Other Expense category.

Now we'll need to record the depreciation using a journal entry. Please refer to your accountant in doing this step to ensure your records are accurate.
Furthermore, you can also consider recording a loan for an asset in QuickBooks Online if you want to buy a new expensive asset.
Let me know if you need help with anything about assets in QBO. I'm always prepared to help you.