I have seen this function at xxx file manager:
The folder tree scrolls automatically to the left or to the right to show the names of the folders.
Your video doesn't seem to work, but the options in Preferences / Folder Tree / Options / Horizontal scrolling style might be relevant.
No, it's not the same function. When I scroll vertically the folders move horizontally to the left or right by itself.
That is what one of the options does.
To clarify, the video shows him dragging an item onto a massively nested list of folders with extremely long folder names. As he goes down the list of folders with the held item, it's scrolling to the right.
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Correction: It's what the automatic horizontal scrolling option does before Windows 10, where Microsoft broke TVS_EX_AUTOHSCROLL and made it do nothing, because if they aren't using something anymore, why should they keep it around, test it, or even document that it has been removed (if it was on purpose; who knows)? 
Here's the current version of Opus on Windows 7, where TVS_EX_AUTOHSCROLL works:
Microsoft introduced TVS_EX_AUTOHSCROLL in Vista for Explorer's folder tree. We implemented the flag in Opus for parity, although it never worked that well in our opinion, which is probably why Explorer stopped using it again in Windows 7. We kept the option because there was no real reason to remove it. But now that Windows 10 has broken or removed the feature, we'll just remove it.
It was more annoying than useful to most people. While searching for the flag and any reported issues with it, the only thing I found other than Microsoft documentation (which still claims it works) was people complaining about Eclipse using it, and that it was horrible in both Eclipse and Explorer, until Eclipse removed it in a patch:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=164437
I think most people felt the same. So we'll remove the option. It was never good, and now doesn't work.
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I've found a way to get the auto-scrolling option to work again, although it requires turning the horizontal scrollbar back on when it is used. (Not having a scrollbar was half the point of the way it worked in Explorer in Vista, so that's strange.)
We might keep it, although I'm still not sure it's a good idea, or that anyone was using it, given no one reported it was broken in Windows 10, and no developer has mentioned TVS_EX_AUTOHSCROLL on the web in about 12 years, despite the OS behavior change which would've broken everything using it in the way it was originally intended to be used.
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After 10 minutes of testing it: No, we're just going to remove it. It doesn't work well anymore, if it ever did. You end up with the current folder not being visible when a new window opens, as it doesn't scroll far enough right. The choices it makes about scrolling are as erratic and unpredictable as they ever were, and end up being more of an annoyance than a help. There's a reason Microsoft stopped using this mode themselves.