Could we config type exchange rate is user in sap. It’s mean that end user can input exchange rate according to transaction. Example, we have 2 transactions with the same of foreign currency. Could we input 2 difference exchange rates for each transactions in the same day?
Yes it is possible to have different exchange rate for each transaction.
In SAP you could maintain Exchange Rate type to differentiate the transaction.
Some transaction also allow you to input the exchange rate manually within transaction.
When you post accounting document i.e. from Tcode FB01 you can manually input the exchange rate in header part. This exchange rate will save in document level (field BKPF-KURSF).
Similar case when you create PO document from ME21N, you can input manually the exchange rate in header delivery/invoice tab, this exchange rate also save in document level (EKKO-WKURS).