Hahahahahahaha…

SWIFT is a messaging network for Cross Border Payments. UPI is a Domestic Payment System.

Unlike domestic payments, there is no scheme operator for cross border payments, which works through a network of correspondent banks in all the said countries and is subject to different regulations in those countries.

UPI does support foreign exchange.

For these reasons and more, no single country’s payment system, however great it is as a domestic payment system, can support cross border payments. This includes UPI of India or Alipay / WeChat Pay of China or Mir of Russia.

When all said countries get together, they will build a new system to support cross-border payments, with built-in support for forex, multicountry regulatory compliance, etc. As is the case with SEPA and TARGET2, the two payment systems that were purpose-built to support cross-border payments between EU nations, and are different from the domestic payment systems used in the individual EU countries.

PS: The above is true for A2A payment systems like UPI. A card network like Visa, MasterCard, China UnionPay or RuPay can very work globally.