Yeah, it’s not best practice, especially for something as small as a sword.
If your sword is split into X amount of separate objects, each with their own specific materials per part, that’s X amount of draw calls the GPU will have to make to render it. Do it enough, and you’ll end up killing your performance for no reason.
You can get away with doing this a little bit, especially with larger models, but it’s something you’ll generally want to avoid if you can while still maintaining fidelity.