Translating bilingual files consists of downloading the files from SDL TMS, opening the files in SDL Trados Studio, performing the translation and then uploading the translated files back into SDL TMS.
Uploading translated bilingual files In SDL Trados Studio, export final bilingual files using Project > Batch Tasks > Generate Target Translations. If you want to update a local SDL Trados Studio Project TM in parallel, choose the option Finalize. You can create a ZIP with the bilingual files for upload so that you only need to upload a single file to SDL TMS.