In order to apply for foreign universities, I translated my academic transcripts and certificates from French to English, and the sworn translator used the term "Computing" instead of "Computer Science" (French for both terms is "Informatique"). My question is: Does the difference between the two terms really matters? or do universities use the list of subjects taken to decide whether I have the prerequisites or not?
It might matter more or less, depending on the particular subject in question, as well as the given translation. Even though the terms that designate "Computer Science" were changing multiple times throughout its history (the name of the field has a rich history and interesting etymology itself), there is a standardized set of terms that people usually go by.
Unfortunate translations that might lead to using terms that are not widely accepted or using terms in a wrong way, might make a difference, depending on the situation. Therefore, even though they might not make a big difference in what they convey, they might make the overall interaction (e.g. a university application) look less professional and it is best to avoid them. As for the concrete example you've mentioned, even though a degree in "Computing" probably can be easily disambiguated as a degree in "Computer Science", it would still be better to make sure the translation matches such widely used term, due to reasons of thoroughness and professionalism of the applicant in preparing an application. ("Computing" has a more general meaning, which does not imply science of computing, as mentioned by Dave Kaye.)
I had a similar experience with translations of my academic transcript, where the sworn translator incorrectly translated terms like "network" and "security". (I think these terms are ambiguous in multiple languages.) I resolved the issue by explicitly checking whether the translations matched "common sense" and pointed out the right translations to the translator. (It's always good collaborate with the translator, which might not be familiar with the specific technical terminology, as mentioned by aparente001.)
Of course, this also depends on the person, the institution that evaluates your academic transcript and its translation, as well as the context. My personal opinion is that in most cases of university applications, these should not matter too much overall (unless they represent a sign of things like negligence and misconduct): 1) translated names of subjects in Computer Science cannot get too ambiguous; 2) you usually get a chance for explaining any potential misunderstandings (e.g. during an interview). Also note that, as far as I know, in most cases, universities require original transcripts as well, thus any "alarming" ambiguity might get resolved without further intervention of applicants.