Castello
The Original Chef Kitten
SemblanceSynder
Because Elizabeth and Adela are both dreamweavers for the main purpose of healing, I think they would have crossed paths at some point and bonded over their shared abilities. Also, I think it would make sense for Xander and Elizabeth to have brought their ill father to the herbal shop run by Adela's mother at some point for some herbal remedies. Adela helps out at this herbal shop by using her Sognial magic to create warm, happy illusions to aide mental pain as well as offer a peaceful sleep, so perhaps this is where she first met the twins?
Also, after Adela finds out that Elizabeth and Xander are from Meridania, she would be very intrigued to hear about their travels and stories, which could further their relationships. This would probably be a refreshing change of attitude for the twins, being from Meridania and all.
Castello
For some reason, I can see Adela and Ricky became very close friends honestly. I think their personalities have just the right amount of differences and similarities. She would be quite fond of his optimism and be able to discern his modesty and kindness. They both have this urge to be there for others, as they are often the first people to console someone who is upset. Whereas Ricky is hotheaded, impulsive, and a poor reader, Adela is more soft-spoken, observant, and enjoys reading. Likewise, whereas Adela cracks under pressure and may lash out in stressful situations, Ricky stays calm and fearless. So I think their strengths and weaknesses complement each other well. Also, neither of them use their magic for combative or harmful purposes. His heavy dependence on charms would also make it Adela's life mission to convince him that he can still be his same old confident self without them.
I know you said that parents may view Ricky as a little off and traditional kids would shun him, but Adela is naturally drawn to those who are different. Perhaps they were each other's first friends and grew up throughout their childhood together? Although I do think Adela's mother would be completely okay with her becoming friends with Ricky, Adela's father may have some qualms. Anyway, let me know what you think b/c we could totally go a different route as well!
MrBossMan
Hmm I can't really see Adela and Lukas becoming very close, but because they both grew up in Bordissa together, they would at least be acquaintances and friendly with each other. She would definitely be one of the villagers who knew Lukas well enough before he joined the army to recognize the drastic changes in his personality when he returned. Would he come to the herbal shop that Adela's mother owns to deal with his post-war mental/emotional pain? Adela helps out here with her dreamweaver abilities, so perhaps they reconnected that way after the war
I think that'd work out pretty well. They both struggle with some internal conflicts so they have a basis to relate to each other. She would probably be an important friend growing up because she could begin to understand why he acts to weirdly and why he is obsessed with his charms and routines.
Looking at your twin, I think Ricky would be the type of person who would piss Augustine off. They might have a little rivalry, but it would always be Ricky being one step behind. I can see their conflicts resorting in physical fights when Ricky is unable to intellectually keep up. However, there might be the slightest bit of respect coming from Ricky's side (can't say anything for Augustine) if only for his relation to Adela.