The only difference between the NTSC and PAL down-throw is the angle, which was changed from 80° to 60°. Knockback and hitstun are the same. Because of this and the fact that DI changes the angle by up to ~18°, you can still use info for the NTSC down-throw since no DI in NTSC roughly equals DI inwards in PAL and DI out in NTSC roughly equals no DI in PAL.
However, most of the time it's best for the opponent to DI out anyways. The change was made to take away her chaingrab but it resulted in removing almost all true combos out of grab if the opponent DIs out.
I haven't tested it, but judging from experience, you can combo peach, samus and puff with dash attack or run->instant fair from around 0-15%, even if they DI out.
The changes also makes techchases on captain falcon, falco and fox much more difficult. They too want to always DI out. That way, they reach the ground much quicker and land a good distance away from you.
This gives you little time to position yourself to react to all getup options.
IMO you ideally wavedash forward so you can react to tech in place with a grab and tech in a direction with boost grab. It's really difficult to get cover tech in place because they touch the ground so quickly. I remember that if you down-throw falco and fox at 0% and they DI away, you only have about 5 frames of leniency to get the grab given they shine on the first possible frame after tech in place. The leniency increases with % though, about a frame every 10%.
So in order to techchase effectively, you really have to practice :
1.
Acting out of down-throw immediately. You can use a metronome to help you with learning the timing. The animation lasts 57 frames so you can act 58 frames after pressing down, that's 62bpm (3600/58).
2.
Consistently doing good wavedashes. You want to slide right across the ground and spend no time in the air. To see how good of a job you're doing, crouch and wavedash. If sheik remains crouching, you did a perfect wavedash. If you see her "stand up" during the wavedash, you did it almost perfectly and if she's in the air, you need to do it faster.
3.
Acting out of wavedash as soon as it's over. 2. and 3. are closely connected since the better wavedashes you get, the sooner you can act out of them. Again, a metronome helps. Given you do a perfect wavedash, you can act
15 14 frames after the jump input, that's
240bpm (3600/15) 257bpm (3600/14) though I would go with 20 frames or 180bpm as a start.
To practice most effectively, use color overlays and/or the frame counter in the
20XX training hack pack if you have it.
