In order to learn the appreggios, see them as several chords played after each other and play them that way. Don't try thumb-under, just shift your hand from one position to the next and enjoy the existence of movement speed and the right pedal.
And there is wrist rotation too, for huge spans. Rotate your left wrist to the left then spread the small finger to the left as far as possible, then the index or middle finger to the right side, see how far you can reach, then rotate the wrist back and see the span between index (or middle) finger and your thumb. The three notes of a chord can be this far apart (of course not playable as a chord then) and this can be close to two octaves without shifting the hand position - perfect legato

. This works with other fingers as well, feel free to experiment.
It requires a bit of practise to narrow the gaps when shifting, but after a while you will be the only one noticing it - and that is just because you know that you aren't playing perfect legato here.
About "is this for beginners": I think it won't be so beautiful when played by a newbie musician, but an experienced musician who started piano playing and got some control over the instrument should be fine.