3512760 - Setting Different Exchange Rate Type Per Ledger is not possible in SAP S/4HANA Cloud Public Edition

• The option to set varying Exchange Rate Type per ledger (0L, 2L) is not supported. For example, it is not possible to use exchange rate type 'M' for leading ledger, and a custom exchange rate type 'Z1' for 2L ledger.

The system does not support setting different exchange types per ledger.
All currency types in Public Cloud are defined as FI currency. This means that amounts in these currency types are written into table BSEG (line items in entry view), which does not support ledgers. Only table ACDOCA supports ledgers. If there would be a different exchange rate type in ledger 0L and 2L, the result of currency conversion could be different. Which amount should be written into BSEG? This is the technical reason why there must be the same exchange rate type in all ledgers of a company code.

The system does not support setting different exchange types per ledger. 

The exchange rate type for company code currency (currency type 10) is M. This cannot be changed. See SAP Help Portal: Currencies which states "Currency translation into the company code currency is performed from the transaction currency with the exchange rate type M (average rate)."

Posting and Clearing are using the exchange rate types which are defined in currency configuration in SSCUI 103379 - Define Currency Settings for Ledgers and Company Codes. For group currency (currency type 30) and Free Defined Currency the customer can configure the exchange rate type. It is not mandatory to use exchange rate type M for these currency types.
If different exchange rate types are needed for the same posting, different currency types must be used. It is possible to configure the exchange rate type for all currency types except 10.
Currency translation into the company code currency is performed from the transaction currency with the exchange rate type M (average rate).

In S/4HANA Public Cloud the exchange rate type M is fixed for the conversion from Transaction Currency to Company Code Currency. For the conversion to the Group Currency or conversion to a 4th currency e.g. Functional Currency, any exchange rate type can be used. See reference in Blog: Currency Conversion with Prescribed Exchange Rates 

See SAP Help Portal: Exchange Rates

SAP Help Portal: Currencies

SAP S/4HANA Cloud Public Edition, Exchange Rate Type, Ledger, Currency Types, FI Currency, ACDOCA, Company Code, Currency Conversion,  Define Currency Settings for Ledgers and Company Codes, M, 103379. , KBA , BC-SRV-BSF-CUR-2CL , Currency translation / Expiring currencies (Public Cloud) , Problem