rubbing my hands like a fly
look. I GENUINELY BELIEVE Amity would forgive her, and she kinda does in the FTF episode.
Amity is a very selfless and caring character who even tried to appeal to her mom's good side when the whole day of unity thing happened, and Odalia has been the only character she completely cut ties with. Amity knows Boscha is a highly troubled child with anger issues and probably the same obsession with winning, being the best and keep everything in control as she used to be before Luz, so she get her, not justify her, but she knows Boscha needs time and real connections in her life.
Amity is a character that always gives a second chance and won't judge you at first glance if she sees good in you (Alador, Hunter, Lilith, Luz, even the Collector), so having a beef with Boscha would be very OOC of her. I think Amity would encourage Boscha to be a better person and care for those who always stood by their side, but I don't see Ams hanging out with her or the grudgby team anymore. Maybe they chat sometimes to each other about unserious things, and every once in a while Boscha still tries to surprise her with her progress or invites her to play some friendly match with them, and Amity would agree for pure courtesy and the sake of sportsmanship and fun. I don't see Boscha apologizing but being less of a jerk with everyone, her kindness is only directed to herself and her teammates only, and Amity is a constant reminder she can be a better leader everyday.
Also, I believe Amity is the one who invites her to Luz's quinceañera party, and she would show up because, I mean, the human saved her team, is the least she can do, to show some grattitude (giggles).

This is an interesting question, so it is gonna be long answer lmao

I believe Manny has the same curious and carefree personality that would make Luz a little less worried around people. For Emira this freedom has a bad taste because she might confuse it with Alador uncaring attitude. I think also she would be very doubtful with him for her own struggles with parents in general, until Amity goes and talks to her about how good person he is. So at some point idk, Emira (17) comes close and ask "tell, me, was it difficult for you to be a dad?" And a bunch of other questions that makes him truly worried of who raised those children 😭

I think Manny would be fond of her and Luz's friends in general, but this particular interaction makes him ask Luz to invite the Blight kids more often, to hang out, to dinner, anything to teach them how a real family feels like.
Adult Emira I think would view him as a reliable adult who she can trust to help her taking life decisions, and Manny thinks of her as a very responsible figure that need to disconnect from it every once in a while.