OK. Forget completely about stashes. They are not needed for the workflow at all. For you, the work is finished once you commit the strings into the repository. After the commit, the stage is emptied and you can go to the translator again.
To summarise:
- Go to Translator
- Use the filter to select strings to translate
- Translate them
- Go to Stage page
- Propagate changes to other branches
- Commit
- Have a coffee and go back to 1.