There is both a creative and technical side to the world of dubbing.
For the Actor who is dubbing dialogue, it requires a nuanced understanding of the film’s story, as well as the performance of the original Actor in it. While the dubbing Actor can certainly add their own interpretation to the dialogue, they should still honor the artistic decisions of the original Actor to ensure that the meaning and intonation of the dialogue do not significantly differ from the original performance.
Then there are the Sound Mixers and Sound Designers who lay in the dubbed track. This too requires a nuanced skill of not only laying in the track to line up with the timing of the original dialogue but also adjusting the sound levels so that the new track organically blends in with the rest of the film’s audio landscape.