What is the Wuxi Finger hold with which Po defeats Tai Lung in Kung Fu Panda

The Wuxi Finger hold does not exist in reality or even in mythical Kung fu scriptures. It's a script writer's creation. But it is inspired by some real stuff like Touch of Death. It says

The 2008 animated Wuxia parody Kung Fu Panda depicts a "Wuxi Finger Hold", in which holding an opponent by one finger produces an enormous shockwave of energy.

Also, if you look into the Kunfu Panda wikia you will find this -

In a Scholastic News Online interview with "Po", when asked about the hardest move for him to learn, Po answered it was the Wuxi Finger Hold and states that Shifu told him (after having defeated Tai Lung with it) that there actually is no such move; it was just a story that masters made up to scare their students. Po added that he can't recall exactly how he did it, but he feels he must practice.

One strong message of the movie is that "There is no secret". This is put forth through the scroll as well as the secret ingredient soup. From this I think we can figure that the Wushi finger hold is not really a secret.

Also, from the way Master Shifu uses it to induce fear in Po, it seems like a mostly psychological technique.

If you follow the fight between Po and Tai Lung, you could see that it is mostly Tai-Lung destroying himself with his own energy. Po merely throws back Tai-Lung's energy.

What the Wushi finger hold does is create fear in an already agitated Tai Lung who says that you are just a panda, you can't defeat me. This fear coupled with the fact that Tai-Lung really "believes" in the existence of the Wushi finger hold, create in Tai-Lung a very strong belief that Po can destroy him if that finger moves.

The actual move is just a trigger I suppose for Tai-Lung to give his own body the command for self destruction. The skadoosh is probably to denote psychological destruction of the enemy.

Obviously, this is still an animated movie and the actual skadoosh was not shown, so we are all merely making interpretations.

The issue I have with this isn't so much with the question but rather the answers. At the time of asking, any of the above could have been true. But now, it is outdated knowledge because of what we are told about the Wuxi Finger Hold in KFP 3.

We are told and shown in KFP 3 that the Wuxi Finger Hold transports people to the spirit realm. However, that doesn't mean that they are sub-sequentially killed. We have only ever been told that Tai Lung had been "skadooshed" because it could only be implied that he is dead. However, with this knowledge now available to us, it is possible that Tai Lung is not in fact dead. Just wandering in the spirit realm after Kai drained his chi.

So, there isn't really a correct answer to give on this topic. Everything comes down to interpretation and implications.

From Kung Fu Panda 3, we learn that Tai Lung has been sent to the spirit realm where he was not able to escape. We also find out that Tai Lung may have met Kai in the Spirit Realm as we see Kai carrying Tai Lung's chi.

the wuxi finger hold destroyed Tai lung, in an episode of kung fu panda Po meets Tai Lung's nephew. Po tells him he skadooshed his uncle(TL), which tells that Tai Lung exploded in the end. If he was brought to prison or somewhere else in China, Po would have interpeted it different to TL's nephew. Plus his nephew get's angry and pushes Po down a cliff, this conclusion shows Tai Lung is dead.

It was a variant of a "Quivering Palm" and basally turned Tai lung's Chi into a nuclear bomb reaction in essence blowing him up into pure energy spontaniously

According to Kung Fu Panda 3

The Wuxi finger hold sends the person to the spirit realm. So that is where Tai Lung is at.