Wendy's. I feel like that performance was the least awkward one, like alot of Chanyeol's duets with girls are a bit awkward but Wendy's wasn't as- Yeah they're from the same company but still.
And I feel like her voice doesn't overpower his, like in the offical audio hes sort of the back vocals behind Punch during the chorus but you can hear his voice as well. And their voices blend well together.
SM has been pairing those two up for performances so I hope in the future they'll do an actual new song together.