I'm interesting about a new feature in the game accordingly to the video of playtrough highlights, so please could someone explain what is "charging" and how it works in the battle?

There is an ability called "Charge". May that's what you mean. Fighters can have it.

I'm interesting about a new feature in the game accordingly to the video of playtrough highlights, so please could someone explain what is "charging" and how it works in the battle?

 

Might you mean "Empowering"? If so it's a new per rest resource that you can use (once per encounter) to make an ability more powerful or to return half of your classes resources.