Why don’t you install flatpak on Ubuntu, make the packaging migration before doing the OS migration so you can evaluate your workflow with the new packaging system? Afer you’re used and confident with flatpak, backup and restore the flatpak folder into fedora and you transition should be smoother (don’t need to worry with 2 stuff at the same time)
Wait and see you distrohopping every month for years ending up in a boring stable distro.