Reliable rumor source Nokishita indicates (Japanese) that Sony is registering a new body, but has not in the registration provided any details. The usual suspects of governmental registration agencies (Russia, Indonesia, etc.) do not appear to have the body registered, so the registration likely comes from an early registration at one of the more obscure registries.
Not terribly reliable rumor source Photar.ru (Russian) reports that “it is reported that…” the new registration may refer to an upcoming A9 mar III. SonyAlphaRumors matched up this new rumor with previously rumored A9 III specs that include a ~50 megapixel sensor, which would be needed if the body were to support 8K video.
Professional photographers have been expecting – or at least hoping – for a real upgrade to the original and much-vaunted A9 camera. An A9 Mark II version came out a little more than two years ago, but was largely a reskinned A9 with better ergonomics and an increased mechanical shutter frames per second rate of 10 FPS. Both versions of the A9 to date have been highly praised for its unique sensor features (pictured) that allow for very fast read-out, minimizing rolling shutter effects and allowing the camera to be used for a professional action photography uses. This was unique among mirrorless cameras until the Canon R5 launched in early July of this year.