That's not usually the problem. Usually you can generally do this on any distro, even ones that have a higher level of integration with their DE.

The problem is more likely to be issues caused by overlapping configurations and base libraries that can cause weird issues if they aren't swapped out or kept default. If they aren't default and are managed by the package manager, usually the package manager will mark it as modified and often won't touch it unless you purge the configurations. Some will ask and some will straight up nuke em.

To me the problem is actually removing the old one. You can easily uninstall gnome, but it will leave behind config files and various data. It's less clean.

Also, there's an overlap in the libraries required by DEs, so you should use the "replace" option in you package manager (if it has one) to let o t figure out the best way to uninstall one and install the other.

AFAIK Fedora comes with Gnome and KDE, both in Wayland and X11 version, out of the box, and you can just select one when logging in.

I'm sure they all allow it, but some make it awkward enough that a reinstall might be a better option.