I scan negatives using a Coolscan V that gives me TIFF files. When I open these in darktable, it defaults to the v3.0 for JPG/non-RAW input. Is this the right order to use for such images?
Those TIFF files are not raw images, so this is the correct order. The most important bit is that input color profile comes early (before exposure), so the image content is covered into the working profile (linear Rec 2020) as soon as possible, undoing any transfer function (‘gamma’). Raw images are linear to start with.