UPDATE: For Odoo 16.0, 17.0 and 18,0 you can now leverage the Accrued Expense Entry option in the Action Menu when you select any Purchase Orders awaiting Bills.

ORIGINAL POST:

When Odoo is configured to value Inventory automatically, every time you debit Inventory during the receipt of products from a Vendor, the expected AP (based on the purchase order) is credited to the Stock Interim (Received) account and this is a Balance Sheet Account.

This can leave a balance in the Stock Interim (Received) account during the time between receipt of product and recording of the Vendor Bill.

If you needed to move this balance to another account for accrual purposes (and then move it back) you could do something like this:

Review the Trial Balance to see the amount:

Create a Manual Journal Entry to move / re-class it (this same approach applies to payroll or other obligations you want to show)

At the time of posting, you can also choose when to reverse this entry, by clicking the REVERSE button:

You then end up with a draft entry that will be automatically reversed on the date you chose:

You should also review:

The Cut-Off button available for Revenue or Expense Journal Items on a Customer Invoice or Vendor Bill that allows you to move a percentage of the Revenue / Expense to another period through an accrual account.

In this example, we pay $25,000 a month in rent on the 25th of each month which covers the 16th of the prior month to the 15th of the current month, so we want to book 50% of it in the prior month. 

This same Wizard can be used to recognize a portion of other expenses and/or income at a future date as well.

Deferred Expenses and Prepayments at https://www.odoo.com/documentation/user/14.0/accounting/payables/supplier_bills/deferred_expenses.html