This is the GuoGuan Xinghen TSM, it can change size, it is also a 2x2.

I'm not a fan of this puzzle. By the standards of modern 2x2s, the turning is extremely stiff and slow. Even after a bunch of DNM-37 the turning is still slow, and the puzzle feels very blocky. The tool is too large to properly fit the caps of the pieces so it just comes off the cap when you pull, rather than removing the cap from the puzzle. It took me a good deal of struggling to get the caps off - I had to awkwardly pinch the ends of the tool to the cap to remove it. Once the caps are off the size adjustment works, but is difficult to turn (the mechanism looks kind of like Moyu's dual adjustment system). It's much easier if you pull up on the round piece, turn it, then push it back down, but this isn't very intuitive looking at the mechanism. While the size changing gimmick is cool, this puzzle doesn't compare favorably to other modern 2x2s; even my $5 meilong m (after proper lubing) turns much better than this $15 puzzle. I hope to see the size changing feature in other puzzles in the future, but for now I'll pass.

I got this with the $10 Mystery Cube. The cube is a very bad performer, cubes like the Meilong M and the Valk are far better. Also, the Size Changing System sounds good on paper, but in practice, it is terrible. There is barely any instruction on how to use the tool. No matter what, this cube is gonna have messed up stickers by using the tool. The tool will randomly explode when you're trying to use it. I used this cube for 10 minutes and then put it away to maybe sell or give to a friend. This cube is at most worth $5. On top of this, the magnets are very strong, something not good for a 2x2. I really have nothing good to say.

This is a good 2x2, while the performance is nowhere near comparable to cubes such as the Valk 2 or the gan 249 it still performs well.
The adjustable size is a very interesting feature that works very well. As far as i can tell there is no difference in performance between different sizes.
My main complaint is that the strength of the magnets is a bit too strong for how slow it is. But other than that it is a pretty average 2x2.
Also, it doesn't come with instructions, which isn't too big of an issue but it could take a bit to figure out how the size adjustment works.

You pull it one of the corners and you see a sizer. Then you move it and then the corner will be sticking out, if you want your cube popping out you take out all the corners and put it to your liking.