Had no issues setting up my US-issued Chase (CSR) visa as the default payment method on DiDi. However, when it came time to pay, it took a bit of trial and error to get the payment screen to load.

Unlike Uber, payment doesn't occur automatically at the end of the ride. Once I got the payment screen to load, it was entirely in Chinese. I just showed the screen to my driver, he tapped the appropriate button and then it progressed to an English page where I did the final payment confirmation.

Worked just fine in the end, but a few tense moments trying to figure it all out. This was back in May of this year, so perhaps this issue has been resolved since then.