A recent Weibo post confirms that OnePlus Ace will be launched this April 21, 7pm in China. It is also shown on the official poster the design and looks of the camera. Aside from that is equipped with a triple camera, it also has flat edges and no alert slider.
We can see from the poster that the OnePlus Ace will sport a flat side frame, quite similar to the side frame of current iPhones, and a triple camera setup on the upper left side with some groovy lines on the left rear side of the phone for the aesthetics.
In terms of specs, OnePlus is yet to confirm it. There are speculations that the OnePlus Ace is actually a rebranded version of Realme GT Neo3.
We expect more details to be released until the launch so stay tuned.