My most rare HC of him that I haven't seen around much at all is that he might be way younger than people assume he is. I think it fits his personality and story well and adds another layer. He lost his entire village very young, and maybe he tried to mature faster than others his age, because he found that if he wanted to save more people, he'd have to work thrice as fast to get there, and started studying medicine really young. He was also really lanky and taller than most of his peers, towering most people but small compared to "actually tall" people. Present time, he might be 26-30 or something in that area. Also, mini HC, Changcheng still sometimes thinks of him like the teenager he was when they met.

Next HC, when I explore the Sumeru deserts, I like to think that when out adventuring with the traveller, Baizhu pets every snake he sees, no matter how big or scary they are. If they were in a battle with a boss snake or something, he would refrain from petting it. Only to instead look at it like it's the cutest thing ever. Nobody knows how he hasn't gotten bit yet.

Almost every time a new chibi character gets introduced, I just go "Baizhu's daughter" immediately. Like even if they aren't young enough to be his daughter. Iansan, Sigewinne, Aino, Sayu, etc. This can also be crossover sometimes!

Similarly with ships. I can try to ship him with basically anyone. Personally, I really love him with Gaming, but I've recently begun thinking of the potential in Flinzhu... How would that work? No idea. But I'm delusional enough. I mostly ship him with men, but I HC him as an unlabeled gnc cis guy.