This is the one we use most when I’m not feeling great:
The way I would describe it is:
He lies on his side with legs slightly bent (experiment with this). She lies on her back at about a 45 degree angle to his body (that lines us up but you’ll need to play around with this too). Her legs go over his hips / thighs. It’s very comfortable and puts the back and hips of the woman into a neutral position.
Slightly surprisingly, standing positions like this work quite well. We use the edge of the sofa / a wall, door frame or something rather than a chair because the chair would probably fall over!
Or things involving the edge of the bed like this work well for me.