Secret identity in Glorantha: How?

Hello fellow Gloranthphiles

I like once in a while to adapt book, tv-series or movie subplots or elements to include in my RPG sessions. 

I find it hard to adapt some elements i would LOVE to gloranthaise, especially situations in which one person seem to be one thing, but is in secret totally different. 

For instance:
The Padme Amidala and her servant Sabé. They swap roles, so that Sabé pretends to be Queen Amidala, and Padme pretends to be the servant, to "spy around". 

Gloranthan set up: 
An esrolian Ernaldan noble women and her Babeester Gor servant. It is easy to imagine them switching places for a short term in the way Padme and Sabé did, but in longer time periods their cover would blew very fast. 
Same premise: A rich Issaries trader and his Humkati body guard. Also their cover would blew very fast. 

Their bodies are decorated with runes, which are obvious very different from the runes of their counterpart. 
They have different moral codexes, which could cause problems: The humakti might not be able to keep of the cover, if the has to lie, or if he has to act unhonourly to keep it up. 


Another thing is inflitration: 
What about a Sartarite spy in Lunar ranks. Not minor foot soldier, but a Sartarite which does everything to get promoted and climb in the ranks (and trust) of his Lunar superiors. Only to run off with the informations he has gotten in his high ranking position, OR using his high ranking status to get near a Lunar dignitary to kill him off. 

Same the other way around: A Lunar soldier (officer) which tries to infiltrate the Sartar rebels. Or an Irrippi Ontor trying to infiltrate a Lankhor Mhy temple. 


How would YOU handle such a situation?

P.S.: My main inspiration why i was wondering about this topic wasn´t Padme and Sabé but the indian movie "RRR", but since i don´t assume that many of you (if anyone) has seen it, i used the Star Wars swap instead.