I am printing large format images on LF printer, books, magazines, brochures, etc. for a decade now with Scribus, and never had a problem.
Scribus generates the cleanest PDF code, offering different standards and adhering to the standards like no other software does.
Though I've purchased Affinity Publisher 3 years ago, I've never used it for real world print jobs, because it is too buggy.
Long story short: I assume you don't know anything about pre-press, and even worse, you don't know how to use Scribus.