Kotaku‘s played Street Fighter X Tekken, but from the sound of it, nobody outside Namco will playing Tekken X Street Fighter anytime soon.
https://kotaku.com/one-illuminating-hour-playing-street-fighter-x-tekken-5790848
According to Capcom’s Yoshinori Ono, each studio is making the game free of input from the other studio.
https://kotaku.com/how-street-fighter-x-tekken-controls-and-why-its-not-st-5790846
Capcom is developing Street Fighter X Tekken, which puts rival fighting game Tekken in the SF, without Namco’s input. Likewise, Namco is developing Tekken X Street Fighter, which does the reverse, without Capcom’s input.
Capcom has something to show for the fruits of its efforts. Namco? Namco is busy.
“We really haven’t started on Tekken X Street Fighter,” said Tekken head Katsuhiro Harada. The studio has its hands full with Tekken Tag Tournament 2 and a new feature Tekken film.