I filed these documents as a ‘package PDF’ like:
Russian ICF v 2.0 20200311
Russian ICF v 2.0 20200311 – RUS-ENG translation 20200314
Russian ICF v 2.0 20200311 – ENG-RUS backtranslation 20200314
Russian ICF v 2.0 20200311 – Translation Certificate 20200314
Russian ICF v 2.0 20200311 – QA or Cert of Translation 20200314
For some trials, I put a coloured piece of paper between each of the documents to make it easier to navigate.
In the TMF Reference Model, translation documentation is a kind of “progeny record” (this is the term used on the Instructions and Glossary tab). The TMF RM states that progeny records belong filed with their related artifact (as described by Jennifer above).
eTMF systems have various ways of dealing with progeny records, but as long as the translation documentation can be seen as related & is accessible from the primary record that was translated, you should be good.