At least in my field, mathematics, in the U.S. (and probably western Europe) it is stylistically quite undesirable to read from slides, because it makes a person look as though they haven't really assimilated the material. For that matter, I've occasionally wondered who actually wrote those slides that the speaker treats as mysterious, surprising, or baffling.
On the other hand, there are indeed possibly even-worse failures, such as becoming completely tongue-tied, incoherent, panic-attacked, etc. But this scenario won't make a good impression on anyone, in any case.
If one's command of the relevant language is so minimal that one can do no better than to read the slides... it still may be better to not read all the slides, but just emphasize the high points, rather than look a bit silly. After all, people can/will read the slides themselves.
In particular, ideally, the audio portion complements the video. They are different mediums. Formulas are best displayed, not spoken. Complicated English (or other) sentences are best spoken, not filling up a slide with small print that makes people squint to read it... Graphics go on slides...