Supernote: the clearest native DOCX route
Supernote says Manta and Nomad can create, view and edit Word documents. Its built-in workflow includes a keyboard mode for revising, adding and deleting text, plus a handwriting mode that can turn written input into typed text. Reflow can rearrange text to fit the display instead of forcing you to pan across a desktop-sized page.
This is the most direct option here when the file must remain a DOCX. It is still a focused tablet, not desktop Microsoft Word. Treat it as a good tool for drafting, light corrections and straightforward documents. If your work depends on tracked changes, unusual fonts, complex tables, citations or strict pagination, test those features rather than assuming “edit Word documents” covers them.