when you have a gold account, sometimes banks offer an option of exchanging currencies with no added operation cost, using only interbank transfer exchange rate. (proably, this is called TT rate). I guess it has some relation to the rate applied to SWIFT-based currency transfers and international payments. Probably, the final number is defined by the bank consortium, but which rate is it based on? Is there any internationally defined conversion rate for SWIFT transfers? If yes, is it possible to see its history and correlation with the stock exchange rate?
No, there is no internationally defined conversion rate for SWIFT transfers. Currency conversion rates are determined by a variety of factors, including the current exchange rate, bank fees, and other market conditions. It is possible to view the historical exchange rates for a given currency pair, but it is not possible to view any correlation between the SWIFT transfer rate and the stock exchange rate.