If you could add any support to fe3h, between which character would it be and what would it be about?
What a great question.
I am terribly Hubert-biased, but I do think what I'd most like to add is a Mercedes-Hubert support chain. The reason I'd choose that is because it would bring out sides of each of the characters that people tend to downplay or ignore.
In my mind, the support would nominally be about Jeritza, and through him delving into deeper topics. Hubert is CF-exclusive and so of course if Mercedes has a support with Hubert she's reunited with her brother.
The C support would be like this: Mercedes approaches Hubert saying that she wants to reach out to Jeritza because he seems lonely, and Hubert seems to talk to him and get along with him, does he have any suggestions? There's this undercurrent of "he's my brother but I haven't seen him in years, and you've been spending more time with him as he is now, can you help?" but it's unspoken because at this stage Jeritza hasn't yet confirmed his identity. Hubert advises her to focus on the practical. Help him train, or help him with weapon maintenance, stuff like that, because doing concrete things to help people is the best way to show you care.
B support: Mercedes tells Hubert that she tried doing as he suggested, and Jeritza appreciated the help, but his affect toward her didn't change. She worried that he wouldn't know how much she cared, so she hugged him and told him how happy he made her feel. And that's what really got through to Jeritza, more than the practical approach. Has Hubert ever tried doing that with people he cares about, instead of just doing practical things to help them? Hubert is flustered, upset, and tells Mercedes that such expressions are unnecessary and a waste of time when his actions clearly show his devotion.
A support: This time, Hubert approaches Mercedes. He tells her that he was inspired by her to tell Edelgard how much she matters to him, and it was as if all the years had fallen away, and they were children together and happy again. Mercedes says that that's how she feels with Jeritza when she tells him how much she loves him. But she also mentions that she's learned a lot from what Hubert told her. Training with Jeritza and helping him take care of his swords helps her feel useful and helpful, when she's spent so much of her life feeling useless and helpless. She says that Hubert spends so much time being helpful and useful for others, that she's going to try to be useful and helpful to him.
That's my concept, but I can easily imagine other equally good support chains between them. They could talk about their feelings about the goddess and religion, and clash about that. They could talk about being spooky! I can easily imagine a whole support chain about that. I just think these two are so fascinating bouncing off each other.
