eBay sellers are calling Xbox One with 1TB drive as "XBox One X" or "XBox 1X" for short....

Then the correct name for Series X should be: XBox 2021 with SSD and 8K resolution. Oh well, too confusing to call the Series X such a close name to "XBox One X Enhanced" when it's at least a 5 year technology advancement......I preferred when MSFT called versions of Windows by the release year, but I also understand that with Windows Update, they keep the various versions updated for security and added features.

eBay still has a refund policy generally following the law for returns within 30 days for almost any reason.

Yep, there's definitely a One X as I have one sitting in my cupboard right now...and a fair amount of games were even Enhanced for the One X and are listed as "One X Enhanced" such as Forza Horizon 3:

And if you want the spec sheet, courtesy of Digital Foundry:

I think consumers get confused with the Microsoft's naming conventions of the Xbox hardware. The original Xbox from 2001 was simply called an 'Xbox', MS couldn't call their next machine the Xbox 2 (called the Xbox 360) because Sony's next console was going to be called PlayStation 3.

Hence the similar (and perhaps confusing to some people) naming convention of all the next generation Xbox consoles after the original machine. The Xbox One X was upgraded version of the Xbox One with more powerful graphics processing capabilities.

Xbox One X is a genuine Microsoft console. It was officially released in November 2017 with a limited number of pre-orders being released as a Project Scorpio edition.
Another limited edition of the console was the Cyberpunk Edition.

The Xbox One X was released as Microsoft`s most powerful console to date at the time.

It's actually not fraud. Xbox One X is an official name. It's one of the versions of the One. https://www.xbox.com/en-US/consoles/xbox-one-x