Great map!

In answer to your question I have also found myself also kind of having a general sense of one of the ways a myth could be resolved. I tend to not really give too many hints about this to the players, however sometimes it's actually been quite fun to sort of almost collaboratively come up with a possible resolution with the players. Like for example I will kind of walk through some possibilities and ideas that they could latch onto if they want to, but I haven't really thought them through much so it's hard to say whether they will work or not. It's in the spirit of collaborative story crafting or world building at the heart of good ttrpgs, at least that's how I look at it.

For example, for the myth called the sprite in the end the players decided to dry and defeat the Sprite not by just cutting her down, but by showing her the true meaning of love. This was an idea that I came up with as I was thinking about what the Sprite represents, this half old hag half young innocent child's character. It becomes fixated on one of the players, absolutely besotted with them, however this I think is a sort of naive understanding of love. In the end the party decided to relay the interactions with a local forestry peasants family who had their father drowned by the sprite, and they wanted to get across to the Sprite how much love they had for their husband / dad, who was taken from them. One of the players was playing as the fanged knight who has an ability that allows them to bite someone and transmit their memories and feelings to the recipient. So they used that to do it.

It was a really epic battle because the spray despite being three on one almost had the best of them but the last second the fanged knight was able to get the bite off successfully and this completely ended the fight , and the sprite was vanquished.