Gnome has an extension called GSConnect which is their re-implementation of KDE Connect. I have in my tablet and phone, and it's flawless.
But don't change yet, give me until the weekend, I'll spin Fedora with KDE in my laptop, and come back with my experience with FlameShot.
No need to change if that's what you like and it ends up working.
Flameshot does require some tweaking to work anyway, so I'll need check if it's the same in KDE.