Short, honest answer first: you lose nothing critical if you write your book in Scrivener, Word, Papyrus, or anywhere else and then have it translated by Literaxis. Upload accepts DOCX, EPUB, and TXT — Literaxis Studio isn't required to use the translation service. That needs to be said clearly before anything else.
What changes if you use both anyway
No friction at the handoff. Write directly in Studio and the export-import step disappears entirely — chapter structure, characters, and scenes are already there when you click "Translate." With external editors you need a clean export (leftover formatting artifacts in DOCX files are the most common reason for a bumpy upload).
Discount tiers. Studio users get a permanent discount on Literaxis translations — 5%, 10%, or 15% depending on plan. That applies even to books that weren't written in Studio, as long as you have a Studio account. So it's not an exclusion criterion, more of a bonus.
Style consistency across multiple books. If you're writing a series, it helps when character name spellings, recurring terms, and your narrative voice don't drift between book 1 and book 3. The voice profile that grows with each translation benefits from source texts coming from the same, consistently structured place — with completely different editors/export workflows per book, that's theoretically still possible, but more error-prone.
What the ecosystem is not
No lock-in. You can download a complete backup of your manuscript at any time (including cover, chapter structure, and supplementary data) and leave Studio without affecting your existing translations. And the reverse holds too: a Literaxis translation doesn't commit you to anything with Studio.
Who actually benefits from combining both?
It makes the most sense if you're planning multiple books — then both the discount and the workflow time savings add up noticeably. If you're writing your first and maybe only book, the difference between "use Studio" and "write elsewhere, only translate" is honestly small — then it comes down more to whether Studio's specific features (Story Heatmap, Manuscript Intelligence, AI writing assistance) appeal to you on their own merits, independent of translation.