Rim swap. Ive heard it can be done. You woould have to really slacken the spokes off and move them over in the correct order to give you the flex to do it.
However, the only thing it saves is having to lace the spokes up correctly, which isnt all that hard to do.
you still need to tension them all up again. As i say, ive heard it can be done, but when ive done it ive just stripped the wheel down to a pile of spokes and rebuilt it.
some will tell you youll die if you reuse spokes, but thats rot. worst case is a couple snap, and then you jkust replace them as normal.
Either way you go, heres the reference ive always used:
https://www.sheldonbrown.com/wheelbuild.html