Sasha was jumping much better 3Lz-3Lo last year. You can compare it with that or with Alina's 3Lz-3Lo at JO, and you will see they didn't perform them as good in those competitions this season. 3Lo combo is a very tricky element and it is often UR on a judging review, so the point is to jump it silky and smooth in real time that judges don't push the review button on it
Yes, and Alina is an expert at having them smooth. In replay they are always borderline UR though.
I think in Anna's case, her problem is that they are backloaded. You can see in warmup she can do the combo with a nice running edge. In her programs she is probably a bit fatigued when the combo comes...