Official and canon are two different things, remember. Just because it's official art doesn't mean they're married or even in a relationship in the stories, just that it's put out by the company and author as official promotion/merchandising.
Holy shit, people ship Winston and Tracer??? That's fucked up, hahahaha
They're just mentioned in the same context. There's no implication here that they're in a relationship.
Even then, their personalities would fit well together and I think I could appreciate a Tracer x Winston ship if the unpleasant implications were worked around (e.g. a romantic, asexual relationship between the two).