The leShay (originally Epic Level Handbook 202-3) was overhauled during the 3.5 revision, but its supernatural ability leshay weapons remained unchanged:
Each leShay carries two personal melee weapons that he or she manifests from his or her own life essence. The weapon can change form as he or she shifts from class to class, typically appearing as a bastard sword (one in each hand). When not in combat, the weapons simply do not exist, but leShay can “draw” their weapons from nowhere as a free action. LeShay weapons are considered light weapons for a leShay, regardless of their size.
The printed and SRD leShay has the feat Power Attack, but can the leShay actually employ the feat Power Attack with its leShay weapons or must the leShay employ an actual 1-handed or 2-handed melee weapon if it wants to benefit from the feat Power Attack? That is, because the leShay weapons are considered light weapons for a leShay, should the weapons also be considered light weapons for the leShay's Power Attack feat?
"Who cares?" I'm considering a leShay as an archvillain for an upcoming campaign. The creature's weaknesses are many—for instance, no energy resistance, no freedom of movement or evasion, no immunity to dazing or stun, no immunity to death effects or energy drain, no extra actions, no movement abilities beyond walking and greater teleport at will—, but these weaknesses can be mitigated by picking for it better feats and with magic items that are part of its CR 20 +8 major items hoard, but I don't know if the leShay needs a melee weapon beyond its 2 built-in +10 brilliant energy bastard swords so that it can deal more than 1d10+15 points of damage per attack. I mean, it probably does anyway in case it encounters an undead or whatever, but still. Keep in mind that despite their 3.5 revision, some epic monsters remain a bit jumbled.
Also, addressesing the meaning of as he or she shifts from class to class would be greatly appreciated but isn't required. It's probably just an editorial oversight, a leftover from a previous draft.