I'm planning to do a 'true nord' playthrough, siding with the stormcloaks and companions and stuff. But It would also be cool to do some Daedric Princes' quests. How are nords relations with Daedric Princes? They don't worship them but are they perhaps raised with a certain hatred or fear of Daedra (princes) typical to Nords? And how is a Nord's position towards Daedric creatures?

Eh I mayne wayyyyy off but ill try to have a go.
Nords are usually warying and distrustful of magic.
Daedric represents not magic, but ideals. As a whole, it would be like any other society in that the people worship, revere, or dispise the daedric that represents their ideals or go against their ideals. Like in morrowind, they worshipped the good and still respected the bad. In cyrodill, daedric worshipping was outlawed? Or looked down upon. Skyrim, im gonna say they worship the 9 and see or view the daedra as a gamble. Not illegal bad, just seen as a gamble with extremely low odds or a cheap way out..
Make sense?
Now this is my opionion as a "whole" of skyrim. I know whereever u go, the daedric will always be worshipped in some shape or form.

So in all, I would say if ur doing a true nord, look at ur characters characteristics and nature and align to the ones who represent those or none at all.

Stay away from Herma Mora and Malacath.

Hircine for one seems to be somewhat important among Nords. Malacath/Orkey not so much, since he shortened the lifespan of Nords. Hermaeus Mora is an old enemy of Nords. Perhaps Sanguine would be a fitting object of Nordic worship since he's the prince of drinking and revelry. Not sure about Meridia though. She seems to be friend to the Aldmer but I'm not sure if the Nords would avoid her because of that.

There might be the odd remnant of Mora or Orkey worship here and there. Sanguine seems fitting because the Nords like to get drunk and rowdy.

Some of Mehrunes Dagon's sphere (like destruction, force, toughening through hardship, the elements, destuctive magic, rebirth, the Apollonian against the Dionysian, untameability and freedom) roughly line up with the old Nordic storm goddess Kyne.

As others have pointed out, Hermaeus Mora and Malacath have a direct place in the Old Nordic pantheon as Herma-Mora and Orkey/Maloch respectively.

Sometimes Peryite appears as a dragon. Make of that what you will.