Hey, just because there are full power loads doesn't mean you need to use them.
Even comparing a generic reduced recoil load in the 500 S&W to the hottest load for the 44 mag.
Buffalo bore 440gr at 1325fps for a little over 1650 lb/ft in the 500 S&W
Buffalo bore 340gr +p+ load that is 1425fps and 1533 lb/ft in the 44 mag.
You can't even shoot that 44 mag load in all guns because of the pressure.
Which means you'd have to deal with more recoil and a +p+ load to even get close to the reduced loads for your 500 S&W, and the 44 mag only gets worse from there, while you still have all kinds of room to play with the 500 S&W and do better.
You've got options, don't ditch her yet, and generally speaking the 500 also has several great heavy high sectional density bullet choices, most others do not. And I don't think there is another at all with bullets that hit that 300+ sectional density area.
So don't handicap yourself if you don't need to, if you don't load, you might contact TII Armory or Aria Ballistics to see what they can do for reduced loads, one thing you can do is get 500 JRH or 500 S&W Short loads, they are reduced loads that work in the 500 S&W mag.
Matt's Ammunition does some reduced recoil loads, Buffalo Bore has that slower 440gr but they also have 500 JRH/500 S&W Short.
**Just note, some have reduced loads that are severely reduced, like 800-900fps, I wouldn't go that low. Though the 700gr at 900fps is actually still throwing 1259 lb/ft, and the 600gr at 1000fps is 1332 lb/ft and would be very easy to manage, like let your child shoot it easy.
See what companies like that can do for reduced recoil loads for you, perhaps try something in the 500gr area at 1250fps or so
I run a custom barreled 5" 500 S&W, one shot, to the brain, let the Glock guys worry about mag dumping and spray and pray, we can just worry about one shot to the brain and end it there.