I have 3 suggestions:
- Embroider the nose
- Make it out of a clay or from another plastic material (there are lots of options in craft stores; do some research about the most convenient one)
- Crochet the nose: I'm really bad at embroidering (and I actually hate it), so when the nose is an important feature of the amigurumi I tend to crochet it. For a hazelnut-shaped, doggy nose this pattern would do: single crochet, double crochet, single crochet in a magic ring, close MR, FO, leaving a tail for sewing. You can use either yarn of same thickness as your project (I would recommend sizing down the hook and working really tightly) or thinner yarn (even embroidery thread!).
If you go onto the internet and search for 'noses crochet' you will find a lot of suggestions. Several even have ones that you can sew on felt with s happy face; a sad face; or anything in between.
Personally, I don't like to put plastic noes or eyes on things I knot or crochet for children.......................:(
It is a beautiful and very complete doll, is so expressive ...
I like to use wire or crewel the nose, you can use the colors you want and make it the way you want :)