Hmm, it took me a while to find specific items to share with you, but these are some of the sets or pieces that I've been able to sleep in comfortably. In your search I'd recommend chemises or babydolls that have a full back and don't have underwire as a general starting point.

Fishnet chemise - This one wasn't the most comfortable ever, but it wasn't bad. The halter type tie was what did it in.
Athena babydoll - Might be a little too dressy, but if you don't move much in your sleep it'll stay situated correctly.
Mesh chemise - Still available for purchase elsewhere. Is really comfortable to sleep in.
Pinstripe chemise - I thought this one was very comfortable as well.
Another pinstripe chemise - This one does have underwire and a decorative slit up the back, but it wasn't that bad.
Pardon my French set - Might still be for sale elsewhere, I just haven't looked yet. This set was comfortable for me to sleep in, but larger breasts will probably fall out of the bottom with too much movement while sleeping.
Heart print chemise - Has a tied keyhole in the back, so it might not be the best choice for sleep if you move a lot. The knot isn't as thick as that of say, a bikini top, so it's more comfortable than that at least.

I got one from JC Penny's that's super comfortable.
But I can't sleep in it because I haven't lived by myself.

for me this is the one:

edenfantasys.com/sexy- lingerie/babydolls-and -chemises/purple-babyd oll-set?tag=1c6effb8-8 4a8-03de-d320-edaaac73 ffae&pnid=71055656