To invest in US stocks, Winvesta needs to receive your funds in USD. For overseas investments in equity (under the LRS), the conversion from INR to USD and the Wire transfer is done by a bank in which you hold an account.
As a part of RBI's cohort, Winvesta enabled the option for funding your global investment account through UPI or net banking. This UPI beta started in November 2021 and ended on January 30, 2022. We are working with our partners and RBI to bring back this feature permanently.