As long as we use ultra-light materials in space, it isn't realistic. But even if we assume the space ship to be built of iron or steel:
You'd want the boots to simulate earth gravity towards your spacecraft while you are on an EVA to facilitate movement etc.
First, if you'd want that, you probably would line the whole suit with magnetic fibres so that the entire suit is being pulled towards the spaceship to simulate gravity on your whole body.
The boots alone would just mean that your feet get pulled down while your body won't. I doubt that this would really help with working in a 0G envionment when just your feet get pulled down. Would feel a lot like in a water tank with weights around your ankles.
Second, to be viable this suit would not disengage and reengage like a magnetic lock that is visible in several movies everytime you try to lift your foot.
It would simply be an always on like earth gravity - which you might have guessed by now - is also always on and would cause your suit to accelerate with 9.81 m/s² towards the spaceship.
On the plus side, this would almost negate the requirement of training every day on a spaceship to combat muscle atrophy.
INSIDE a station, the easiest way to simulate gravity would be to rotate it. No need for anything magnetic around you to give you "gravity". Also inside you'd have the problem that you'd need one plane to be your "anchor". Otherwise you'd lift a foot and it would suddenly get pulled to the wall because that happens to be made of steel just like the "floor".