But It can be done by keeping the controlbehavior somehow, I can't do any test right now.
Json keep hand content and circuit network connection ?
I'm sure by having to do it in two step, some people will have trouble.
But if your solution work keep it, no need to spend a week on that

For blueprint, it can be done but even if you update all blueprint in the world, if people bring old blueprint with blueprint string mod as world is already loaded, you must have a gui button or keystroke to update the blueprint in hand.