But he has a new obvious power he didn't, as Nightwolf wasn't casting the same weapons he always did.
The point is: you are assuming that "new body = new powers/ old body = old powers" even ignoring that Sindel died with no body remaining and that was obvious revenants are resurrected on that pit.
It's just a mess of new decisions that Midway/NRS have been taking on characters origins, there is no exact pattern that we can make an aristotelic sentence.
So does Sub-Zero (ice hammer, ice shield, ice daggers), it means nothing.
Liu still has his Bicycle Kick, Fireball and Flying Kick.
No. The point is the characters that NRS deemed to have stayed the same, NRS kept the same, such as Sindel, Baraka and Rain having the same moves.
Sure, they're NPC and I get that, but NRS could have also given Sindel some new moves in your VS battle with her to signify that she's a new Quan Chi creation, since they don't have to create 3 variations for her.
In MK9, all the dead characters appeared in the NetherRealm in the same way that they died, as a ghost / revenant / zombie or whatever you want to call it, without being resurrected as new creations (see Cyber Sub-Zero), and in MKX, those dead characters, aside from 1 or 2 playable ones (Sub-Zero, Liu Kang) retain all of their original moves.
Kitana and Kung Lao are "what if" characters on the main roster, which is why I didn't count them, as their default skins are non-canon.
Sure, there is no exact pattern, but to me it seems like Sindel, Liu Kang, Kung Lao, Kitana, Nightwolf, Smoke, Jax and Stryker stayed the same.
The only ones that seem to be resurrected, imo, are Scorpion, Sub-Zero and maybe even Liu Kang (I'll give you that one, since he has no burn scars).
They can leave her however they like, but she needs a new body because her old one does not exist.
Didn't Quan Chi bring back her original body out of thin air in MK9, though.
Pretty sure that with his sorcery that he can do the same for Sindel and Nightwolf again, without resorting to
resurrecting them as a new creation in a
new body, in the MKX pit, and having them show up as their former selves.