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14:30 Apr 11, 2022 

If you are making a sworn translation into English, then I presume that your translation will be preceded with a brief formal statement explaining the origin of the document, and will close with your own statement about conformity with the French version. That opening statement should include details of the translation chain: ar (original) --> fe (sworn translation) --> en. Then, because yours is also sworn translation, all of it (including the French translator’s statement of conformity with the Arabic original) should conform exactly with the French version, without any additional explanation. The sentence you are asking about should be translated literally. From the structure of your finished document it will in any case be clear that the sentence forms part of the French translator’s output, not your own.

There’s no reason why you do something similar, even if yours is not a sworn translation: you can begin with a ‘translator’s note’ (NdT) explaining that same chain of translations.
In this case, you might also want to consider including a disclaimer, to the effect that you do not warrant that your translation conforms to the Arabic original.

14:04 Apr 11, 2022 

I'd prefix the AR>FR translator's statement with sth. like "Statement by the translator of the original Arabic document into the French document translated here:". Unless it is made clear by you within your translation that it is a FR>EN translation of an AR>FR translation.