Both actually, Mount Hua sect but they are also knows as plum blossom sect since their martial arts revolves around flashy sword technique that produce Plum blooms.
Warriors from Mount Hua who can create plum blossoms with their sword are called Plum blossom Swordsman
You might be thinking of people who forgot that mount hua sect produce Plum blossoms. That's the thing that was forgotten after the war because the technique disappeared and no one can create plum blossom with their sword anymore.
Also, I think I've read it somewhere that Hua actually means flower or blossom. So, it could mean mountain blossom sect?
its been a while and i have a question: did the plum blossoms have their own sect? or was it just apart of the mountain sect? i mightve gotten lost in translation at some point because i feel like i read somewhere that “the plum blossom sect” was the best, but it disappeared after the war and now the only ppl that remember its existence was the mountain sect. i mightve just made all of that up though. please correct me if im wrong