Deferral defaults
Use the Deferral defaults page to set up default deferral accounts for items and to assign default templates to deferrable items. You can also set up deferral accounts for charges and assign templates to the deferrable charges.
Defer by item
For transactions that have an item (for example, sales orders), you can assign accounts and templates to specific items and customers. These settings will be used as default values when a transaction is deferred. To make the transaction deferrable by default, you must set up the items on the Deferrable items page.
*-> Defer by account
For transactions that don't have items (for example, general journals), you can specify the deferral accounts. When these accounts are used on a transaction line, the transaction is automatically marked as deferred. The corresponding template and recognition account will be assigned to the transaction line.
Reference:
https://learn.microsoft.com/en-us/dynamics365/finance/accounts-receivable/sb-deferrals