I'm kinda in the same boat. Injured my wrist in an altercation, had surgery, couldn't be fully repaired, etc. I have owned a bunch of 9MMs over the past 45 years, to include Lugers, S&Ws, Glocks, HKs, Benelli, CZ, Colts, Kimbers, Springfields, Rugers, a Star, SIGs, etc.
I believe the softest recoiling 9MM, that I'm aware of, at least as felt by the shooter, would have to be the SIG X-5. I have a S&W Performance Center PC5906 with 5" barrel and full size steel 1911 type guns in 9MM that are pretty soft shooting too, but have to say the X-5 feels the softest to me, even with NATO, +P and +P+ ammo.
I have read one very prominent writer who believes the HK P7 recoil feels very soft. Not for me. Recoil with my P7M8 and previous P7, and their gas retarded action, feels very sharp to me. The worst 9MM recoil I've ever experienced was with a nasty, IMHO, little straight blow back 9MM called the Detonocs Pocket 9...ymmv