General transfers from one project to another, or to a group of projects, can be done using the general transfer accounts 40997 / 58497.
Project A would like to give $100 to Project B to share general expenses.
Same department: Entry is input using a journal entry using a source code of O60.
Entry is input using the IDT system. Using transaction type IDJ, Project B would “charge” Project A $100 and use account 58497 for both the Biller and Payer sides of the transaction.