In Gylfaginning Hlin is listed twelfth among the Goddesses, and Snorri tells us : ' Hlin is set over those people whom Frigga wishes to protect from danger. Some take the second stanza in Voluspa : " Hlin suffers a second sorrow when Odin goes to fight the great wolf at Raganarok, " to mean that Hlin is just another name for Frigga, but of course that contradicts her needing to send Hlin to protect people from danger. Hlin, being close to Frigga, would of course be joined emotionally in the happiness and sorrow that is experienced by the All - Mother, and I feel this is why she also feels a " second sorrow ".
Hlin is a Goddess of protection for Midgardians, in the same way that Thor is a protector of Midgard. Just as Thor's hammer is a symbol of strength and protection , so too is Hlin' s name, carved in stone or wood, a device for protection from all dangers. I personally like a walking stick that has her name carved in runes on it for protection.
Hnoss is the daughter of Od and Freyja, and is listed in both Snorri's catalog of Gods and Goddesses in the Eddas, and also in the Thurlur. Snorri tells us that Hnoss is so beautiful that from her name all things that are precious are known. Some also translate the name into the word treasure.
To me Hnoss is much more than just a beautiful young Goddess, or the daughter of Freyja and Od. She is the next generation of Gods and Goddesses that will survive Ragnarok, and rebuild Asgard, and protect Midgard. She will learn from her mother the art of Seidr, and will eventually become even more powerful than Freyja. I see the post Ragnarok Triad as Balder ( Odin ), Magni ( Thor ), and Hnoss ( Freyja ). She will be splendid in her mothers role, and make all the Gods past and present proud of her.
Idunn is one of the most important Goddesses to the Aesir. In Haustlong Idunn is referred to as, " The maiden who understands the eternal life of the Aesir. " Snorri takes this one step further and tells us that she is the guardian of the Golden Apples, which when eaten by the Gods, gives them eternal youth. The Jotun Thjazi, however, sees this as an opportunity to destroy the Aesir and forces Loki into helping him kidnap Idunn and her apples. In Skaldskaparmal Odin, Hoenir, and Loki are trying to cook an ox after a hard days journey. Everytime they check the meat, however, it is still raw. An eagle in the tree above, ( The Jotun Thjazi in eagle form ), is the cause of this predicament. The eagle tells the Gods that if he is allowed a share of the meat he will allow it to be cooked. The hungry Aesir allow this, but the eagle takes too much of the ox, and an angry Loki stabs it with a stick. The eagle takes off dragging Loki just high enough off of the ground for his legs to hit every obstacle he flies over. Loki pleads with the eagle to stop. The eagle agrees, but only if Loki will do him a favor.... an evil favor.
The Jotun Thjazi forces Loki to lure Idunn out of Asgard and into a secluded wooded area with the promise of some very special apples. Thjazi in the form of an eagle snatches up Idunn and carries her back to her fortress. Without the apples the Gods quickly grow old, and start to look for the one responsible for her disappearance. When Loki is found to be the last one to have seen her, he is threatened with violence until he finally agrees to get her back. Loki borrows Freyja' s falcon coat, and flies to Thjazi' s fortress, turns her into a nut, and flies her back to Asgard.
When Thjazi returns, and finds her missing, he turns himself back into an eagle and gives chase. As they approach Asgard the Gods build a huge fire which Loki is able to avoid, but Thjazi flies through burning his feathers which makes him fall to the ground. Once on the down the Gods kill Thjazi for his evil deed.
During the arguing between Loki and the Gods and Goddesses in Lokasenna, Idunn tries to stop the argument that is going on between her husband ( the Poet - God Bragi ) and Loki. Loki then re - directs his anger at her saying : " Be silent Idunn ! I declare that of all women you are the most crazy for men, since you wrapped your arms, washed bright, about your brother' s slayer. " There is, unfortunately no other record of her brother, or her brothers slayer, in the Eddas. A shame, because it is probably a wonderful story.
Idunn keeps her rejuvenating golden apples in an " eski " ( a wooden box ), and it says in Gylfaginning that the Gods depend greatly upon Idunn' s good faith and care. This leads me to believe that Idunn is a very powerful Goddess in Asgard, and one that is greatly respected, and I would think also feared by the Aesir. In her eski literally is housed the very lives of the Gods and Goddesses. Yes my friends, she is a very powerful Goddess indeed, and yet she is very gracious and giving.
Go with Odin's wisdom, Freyja' s love and Thor's protection !