This strikes me as a question that many people may have asked themselves but i couldn't find any direct answer in the books nor online, but maybe I missed something.
I'm going to start running a fan-made campaign in which all characters are sartarite children, and despite that they cannot use magic in account of not being yet innitiated in any cult, I made them choose the runes so they could hint at the character's personality, and two of them said they wanted to have a tertiary affinity with the moon. At first, I plainly forbade it, as I thought that the moon rune wasn't even accepted as a real elemental rune by anyone besides the lunars, so I believed that affinity impossible. But then I realized that the pre-gen character Vassana has a SECONDARY affinity with the moon rune, and that broke my schemes. If Vassana and his lore can be considered "canon", and I don't know why would the developers make the most important pre-gen character to break the universe rules, then the orlanthi CAN have an affinity with the moon, so insted of asking myself if it is possible, I started thinking, "How would an orlanthi react to being linked by soul to the moon?". As far as I know, sartarites not only hate the moon for representing the empire that murdered thousands of their brothers and occupied their country, they hate it most because for them it represents the intention to murder Orlanth, it represents the next coming of chaos; for them, the Shepelkirt is just the new face of Wakboth. Knowing this, wouldn't a sartarite who is touched by the moon feel (or even be treated as) touched by chaos? Wouldn't he hate himself? This is at least, how I have interpreted the lore.
So, I ask for your opinions, and your corrections, as I'm only a newcomer to the world of Glorantha. How do you think the orlanthi treat the individual rune affinity with the moon? How have you treated this in your games? I appreciate any story that involves the topic.