No. MakerLens cannot sync with Etsy or fetch your shop automatically. You export a CSV from Etsy and import it into MakerLens. There is no Etsy API connection and no OAuth.
No. The workspace lives on one device. There is no iCloud sync.
Text recognition currently accepts files from the document picker or drag-and-drop only; there is no photo picker or camera path yet. This makes the feature hard to reach on iPhone. We know, and it is on the list.
Yes. Images over 40 MB are rejected for text recognition, and text or CSV imports over 20 MB are rejected. Supported image types are jpg, jpeg, png, heic, heif, tif, tiff, bmp, and gif.
The CSV must contain a listing-ID column. Without one the import fails, and individual rows lacking a listing ID are skipped.
MakerLens moves it aside as workspace.corrupt-<timestamp>.json rather than deleting it, and starts fresh. Those files are never cleaned up automatically, so you can recover or remove them yourself.