I've been thinking of all the ways Shangquin can parallel Sambucky, just in terms of the characters that comprise the two ships.
On the surface, Shang-Chi seems most similar to Bucky. They're both powerful fighters who were turned into living weapons, which has left both with a lot of trauma.
But Shang-Chi is also very much like Sam; they're both personable and charming while only having a small number of people they trust enough to be truly vulnerable around. Each of their stories features a lot of grief, and both seem to have reacted to their own personal losses by running away (to different extents) from their problems for at least some period of time. They even both have a younger sister who they unwillingly left behind.
Joaquin is obviously very much like Sam, given how he's the new Falcon. They both got into the superhero business out of a sincere desire to help people, and sort of fell into the role of being Captain America's right hand man. And of course both of them enjoy taking the opportunity to be a little bit cheeky when given the chance.
But Joaquin is also very much like Bucky, especially the Bucky we saw in CATFA, who started to re-emerge in TFATWS. They're both nerds, especially about cool tech or gathering information. Each of them saw Sam and decided to latch onto him as much as possible. And now each of them has had a pretty traumatizing near-death experience.
I'm sure there's even more that could be teased out, which is why I love the potential of these two ships coexisting. Imagine all the ways these characters could see themselves and also their relationships in one another.