It seems that most of the drywall mounts that I looked for printed in a vertical orientation, which is not good for strength.
For once, I didn’t reverse engineer anything to design this. Lulz.
https://www.printables.com/model/548516-printable-drywall-mount
Update 8/10 - Added dimension sketches, Added .step file, Added a thinner support ring option that will sit more flush (but not completely)
They expand quite a bit and the little tabs are intended to dig into the drywall to keep the assembly from rotating while it the screw is set.
I suppose you could cut the little tabs off and not use the ring and it would still work. It may be problematic since the main anchor bit is split in half.