Translation:She works as an interpreter between Swedish and English.
Strictly speaking a translator deals with writing and an interpreter works verbally, bur colloquially the terms are rather interchangeable.
For those learning english, from swedish. In swedish it may use the preposition "mellan" which is "between" But it should translate to the english preposition "for" EX: (She's an interpreter for Spanish and English speakers.) or (She translates or is a translator for French.)
It can be both - There is no problem using 'between' or 'for' here in English. In fact, 'she translates for French' seems to be erroneous (although I might just be overlooking a correct usage)
The sentence in English would be better if it was 'she works as an interpreter IN swedish and english'. Using between here doesn't sound right to me in English.