Fenghuang, as in its traditional myth, isn't a phoenix; but we all know that and that's not what I'm arguing here.
Fenghuang, as in its modern understanding by popular culture, is conceptualized as the Eastern phoenix; which is why creatures like Ho-oh from Pokémon or Hououmon from Digimon got attributes from the Western phoenix (enhanced fire properties, regeneration, coming back from death, etc.) in spite of being clearly based on the Eastern bird. This is exactly what I meant when I talked to you about a "globalized syncretism" that has caused both creatures to merge in pop culture such as One Piece; because yes, Marco falls here too, hence why he's clearly designed after a Fenghuang more than a Western phoenix (peacock tail, pheasant wattle, his colors, etc.) to the point his techniques explicitly refer the Fenghuang (with its Japanese name, "Houou", appearing in one of them plus others referring the birds traditionally described to conform it) and took the place of the rooster in that color spread, being the rooster virtually equal to the Fenghuang (which is also called "August rooster").
Don't take this badly because you seem to be a good user, but I'm not wrong here. You sent me a link to a web page; I've been studying this kind of stuff from actual scholar books for years and I don't speak lightly; also, I highly doubt you will tell me something I don't know (in case you thought you would get me with that information about Fenghuang not being the same as the Western phoenix). But if you want to add some fuel to your Hiyori idea, you may want to know that she was introduced wearing a peacock-themed kimono, which is one of the pheasants that inspired the Fenghuang.