ANYTHING is feasible.
I've seen it done so go for it.
Would like to do the same thing myself.
cut and weld job as the rails have a different width on one side and the center section is completely different.
a mk3 golf only differs on the rail width, so its easier, you only have to cut one leg off the old mk2 seats and weld it on the mk3 ones.
There is a good DIY on the vortex for
swapping MKIII seats into an MKII, B4 Passats may not be that different, I think they are wider though. Some info on the rear seats
here and
here, again a B4 Passat is going to be wider than an MKII.
thanks for the links Ziptar, I am planning something like this and they sure help