Animated Weapon

So one of my Chaotic Wacky players wanted to do this. To play an animated weapon.

Here's what I've got on the fly. You're a small construct. We use the standard array to create a character So I'm going on the idea that your soul was used to create the weapon and you have the racial mods of the race that you were before being trapped in the sword (or whatever). The player who wants to try this is leaning towards a longsword.

You're deaf and blind and mute but can use your movement to gesture including somatic components if you gain the ability to cast. You're helpless in an anti-magic field or dispel magic effect. When not moving, you are indistinguishable from a normal weapon of your kind. You don't heal but you can benefit from healing magic and can be repaired.

The weapon can be held and used by a wielder and can use the wieder's senses when in hand and can communicate telepathically with the wielder if attuned.

Following the rules for an intelligent weapon in the DMG. It has goals and can possess a wielder that goes against them. As time goes on being animate and the abilities it gains could become the benefits of the weapon as in the DMG. The player is thinking hexblade warlock. One with an exceptionally hard assignment from her patron.

Any thoughts/suggestions?

1. I wouldn't let him be healed via healing magic. Maybe some other kind of magic - like some kind of conjuration spell that creates objects. He could heal naturally, but for a short rest, a blacksmith can help him use his HD to heal up.

2. I'd, just have him play the sword but through a physical person that's completely enslaved to the item. The DM can randomly have the pesky human reassert control occasionally. It's still a PC but from a slightly different angle. If the character dies, he's still alive...he just can't move etc...and now he has to find another host...but, sadly, the last host was all leveled up! How will he find a 'worthy' host?!

The reason I suggest this is, I feel, he'll often have a hard time trying to do the things he wants and will always be dependent on the other players.

3. Disarm him from his wielder occasionally.

1. I agree. Mending or Make whole or the like. 50gp./hp. to repair as with other constructs.
2. This is why even though Animated weapon and Intelligent weapon aren't the same I went with the possession described in the DMG. If she does a warlock, no vocal and no material components because no hands will be a challenge without a possessed wielder. She could use the sword she possesses as a focus.
3. Good idea. If it gets too frustrating there's always rust monsters