On the men's side it's mostly a matter of hoping for surprises. I mean, Martina has shown again and again and again and again that he knows very well how to peak at a championship event even when the rest of his season was mediocre, so even though in his current shape he's far from any favourite, it's never a smart move to count him out. Bonevacia (400m) and the 4x400m team will have to have one or two amazing days plus have the luck that some higher rated favourites don't have their best day, same goes for Comenentia in the hammer. The men's 4x100m might be the most realistic men's medal chance, since they're in great shape (broke the NR last week) and if there's one event where favourites can 'easily' get in trouble it's a sprint relay with dropped batons and stuff.
In short: yes, there are some possible chances, no, none of them is a major medal threat.
This is what I had listed somewhere else for the women:
Schippers (100m, 200m, but she really needs to step up her game, because with her most recent awful performances she's barely even a threat. Of course she has the potential for double gold, no doubt about it, but she's been getting slower and slower every day since switching coaches)
Samuel (outside chance in the 200m, mostly because she's been the opposite of Schippers: improving every race and now even beating Schippers last week)
Women's 4x100m
Lisanne de Witte (400m, not the favourite, but in current shape definitely a chance)
Sifan Hassan (main favourite in the 5000m)
I have no idea what Krumins will be capable of in the 5000/10.000
Visser (100mH, if she can get back to her NR-breaking level that she had in May/early June, before her recent couple of weeks out due to injury)
Vetter (heptathlon)
Yes, the goal of 7 medals is of course far from impossible, but to reach it certain people (mainly Schippers) need to show a whole lot more than they've been doing so far this year. 'Gun to the head', I'd say 5 medals.