Was just talking with Mr Aquaman about this. Hope the below helps:
In terms of the Shinnok match up, sure thing. After the nerf to his meterburn Hellsparks, I don't find him to be nearly the problem he was before. In either Impostor or Bone, you'll have to deal with the vortex, but the vortex, due to the frames, is fairly predictable. Since the low is the fastest, that should always be your default, and then you wait to react to the overhead (which is tough at 18 frames, but feasible). Also, keep in mind that he can only continue to the low combo (at least in Impostor) if he has a meter, so if he doesn't, you can default to the overhead. The throw is definitely a pain to stop and hurts with the damage buff, but if he uses it, it's actually good, since now you're out of the vortex. Really, the Shinnok player should only throw to close out the round, or perhaps when out of meter, so those are two good times to watch for it, teching based on where the nearest corner is. Beyond that, it's important to keep in mind that Shinnok's only viable wake up in Impostor is the EN Shoulder Rush and in Bone is the EN Low Sweep, both of which are full combo punishable. That means you can abuse him when he has no meter, and even when he has meter, in Impostor, the risk/reward for his EN Shoulder Rush is so bad that if he hits you with it, it's not a big deal. Lastly, for his Hellspark pressure, now that it's only +14, you can often jump out, as you see me do at the 38 second mark and 2:12, or armor through, at 2:48:
I hope this video also helps show the rest of what I've discussed, against a skilled player, as I think most would agree that GGA Max is a good representative of the Shinnok community. Despite how useful the move is that Shinnok steals, I think in time most Shinnok players will switch to Bone in the Kotal match up and try to zone him, but that's another conversation. Oh, one last thing, regardless of which variation Shinnok is, you can armor through his 1123 string, between the 2 and 3, which is always fun =)