This is according to a video shared on Twitter by Jordan Khan in which it is allegedly a magnetic wireless charging prototype. At this point, it is impossible to verify whether or not the video is authentic or if the device pictured is even an Apple prototype since there is a lack of branding on it.
A possible scenario could be that this is a development unit that Apple might be providing to third-party accessory makers who want to create MFi accessories for Apple’s products. Alternatively, it could also be nothing at all and completely unrelated to Apple. However, there have been some rumors suggesting that the iPhone 12 could actually come with a ring of magnets in the back that could allow for new accessories, like this magnetic charger, to work.
https://twitter.com/JordanKahn/status/1306641820877807616
Apple has used similar technology in the Apple Watch (and still does), and with rumors claiming that Apple could be moving towards a completely port-free iPhone in the future, perhaps this could be a new charging system that the company is looking to slowly introduce to customers to get them used to the idea of a port-free iPhone in the future.