Assuming you have the "Favourites List" shown (alt+cmd+B) in Safari browser.
That list is customizable in Safari and you can carry it along with your iCloud account, so if you use another computer, your favourites will be there in Safari.
It's basically a folder in the bookmarks.
Is there some BTT inbuilt way to get that list, and create some scrollable in the TouchBar for it?
Like an App switcher widget, but iterating thru Safair's Favorites and produces some buttons linked with/to each favourite
I checked and could not find anything in the available actions to get (any) browser favourites list or bookmarks in general...