Mercia and Orcs are allies?

1- The kingdom of mercia and Ilmara hate each other because of the issue of slavery. If there is no temple of the three in any Mercian city, what kind of religion do they worship? Did the Mercians cultivate the ancient imperial religion, their own seven emperors or do they have no religion?
2- On the map we realize that on the mercia side we have the orc kingdom, but it seems that they do not suffer any kind of discomfort from them. Worse, Varsilia is a little far from their realm, but they are constantly bothered. Are the kingdom of Mercia and the orcs some kind of allies?
3- It may seem like a silly question, but why don't we have a helm of myros?