This looks a lot like that image we had back in 2011. Except maybe they moved to dual engine instead of single.
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This was at CAC. For one thing you can see the J-10 and J-20s nearby.
This prototype also bears greater resemblance to CAC's prototype 6th gen with the three engines. Could have been an early demonstrator of the overall airframe but scaled down.
There's also these "placeholder" images of 6th gen fighter from years ago.
To add a few other images of the mystery prototype from around 2021.
All three (one including your image) appear to be in slightly different positions indicating these sat images were capturing some movement whether under it's own propulsion or whatever is unknown. What's important with these images is that they are associated with a CAC operated airfield and hangars. This object also bears strong resemblance to the recently revealed 6th gen prototype from CAC albeit the prototype is larger and has three engines rather than one or two.