I'm applying to universities. I was thinking to translate "mention bien/très bien" by "with honors" but on my transcripts I had both (on different diplomas), so I would like to know if I can distinguish them
les mentions on French diplomas (funnily enough, I happen to have three of them) means honors. (Not to be confused with mention on legal documents, please.)
Translators (which is what I am) argue a lot about this. Personally, I would used: degree in [subject] with high honors and with highest honors. I also have a mention très bien.
with honors, high honors, highest honors.
I will, however, point out that those terms work for university degrees. If this is for the BAC, and you use the term baccalaureate diploma (for le BAC, baccalauréat) you can use them. I advise against using "high school diploma" with those terms. The BAC= A Baccalaureate diploma (equivalent to high school plus two years).
[please note: I was thinking of translating x as y.
This should be treated as specific and technical terminology associated with a particular educations and examinations system, and not translated.
In a Resumé or CV you list your qualifications exactly as you received them "A diploma mention bien" And you may indicate by means of a footnote or endnote an equivalence with the local examination system "*equivalent to a diploma with high honours". You do this as a courtesy and convenience to the person receiving your CV.
Hiding the actual qualification behind a translation could cause you to be accused of misrepresenting your qualification and lead to difficult questions at interview.