Hilarious things you've found in RAW?

[Promethean]

I'd just like to point out that, by treating a weapon as an animate object except for its HP, flying is an altogether terrible property to dump on an otherwise strong item.
As far as I can tell, animated objects only get a slam attack based on their size. Rug-like objects can blind and rope-like objects can constrict, but as far as I can tell there's no special attack for blunt or bladed objects allowing them to make weapon attacks.
Any reasonable DM is going to say a +1 flaming flying great sword is going to deal 2d6+1 slashing + 1d6 fire, but RAW as an animated object it'd just gets a 1d4 slam attack.

Wouldn't it's enhancements still apply to it's natural attacks similar to the magic fang series of spells?

If not, it has still has HD. Have it take weapon proficiency(its weapon type) as it's first feat upon gaining intelligence >3 and have draw + wield itself.

The latter falls under the same "technically true" RAW as removing your armor and standing inside it for full cover, but we're already in a thread for funny RAW so... ¯\_(ツ)_/¯