The great thing about the noble sword is that the only real canon lore about it is that it is a sacred blade and resided either holodrum or labrynna(depending on the order you play the oracle games in). As for the established mythos for it there's almost an empty slate, with a few exceptions:
The blade wound up in the sacred vault after Ooa/Oos
It's a sister sword to the sword that ghirahim represents
The spirit, adeline, is fully corporeal like her 'brother', but unlike him requires sleep because her sword's sacred power is drained from the magical energy inside of her corporeal form.
Also unlike her 'brother' she doesn't fight. She just provides guidance to her partner.
Im sure there's a bit more but that's all the important stuff.