>>45720809They're the public beta versions that contain nothing special over the final product released a year later. It was a full price 3DS game because it was early access. The story changes from focusing on the evil team to focusing on Necrozma in Ultra, but other than that Ultra contains more features; notably catching all previous legendary pokemon. The story of the first release is a similar enough playthrough to Ultra including all the dialog, but you'll be saying "That's it?" when you're done with the game. Ultra has a 2 new Ultra Beasts, new Necrozma forms, a fixed Lycanroc-Midday, and some new irrelevant exclusive Z-Moves you can't use in multiplayer battles when battling against the early access games.
If you want cheap access to Gen 7 you can buy one of the first releases. If you want to see all that Gen 7 has to offer get an Ultra game. If you want to save yourself don't play Pokemon.