i can’t speak for a method of supporting the camera in his hands, but look into systems with both in body image stabilization AND in lens stabilization. I’m kind of surprised by the shutter speeds with which I can get sharp shots. i have a nikon z5 with in body stabilization and carry a lens with stabilization too. i don’t have a physical disability, but i’m a bit jittery and have noticed a big improvement.

a full frame mirrorless may be a bit heavy, but to my knowledge, olympus and other micro 4/3 systems have very light cameras and lenses with stabilization that are typically marketed to adventure and wildlife photographers who don’t want to carry a ton of weight in their backcountry packs. the 2x crop factor can be great for wildlife since you can get huge reach with smaller lenses. the low light capability is the primary sacrifice with these lightweight 2x crop cameras, but i’m of the mind that a well-composed shot is good whether there’s a little noise or not, and high iso noise can be repaired to some degree with software.

It’s not really the best by any means, but I love my Nikon Z 24-200 4-6.3.

The variable aperture is its main weakness over the 24-70 f4, but I do landscapes, so I’m using a tripod in any low light scenario.

I like being able to take a backpack trip in rugged terrain and never have to change lenses when it’s wet/sandy/dusty/etc. It’s nice to be able to get wide angle landscapes, close-up detail landscapes, and occasional wildlife with the same lens.