Mixing metal finishes in plumbing, hardware and appliances?

I wouldn't think that would be an issue. I have nickel faucet, black & stainless appliances, and not sure what to classify my hardware but it's kind of antiqued. I've never though of it needing to match.

Sure. It’s a matter of making a balanced composition.

Think of it like a vase of mixed flowers.

Yes we are re doing our kitchen and have bronze faucet and cabinet pulls and stainless appliances. Looks great

If you like it, then go for it. I have always mixed metals whether it was trendy or not. Think of it as jewelry for the kitchen. There is ample free help at any kitchen and bath showroom for guidance if you need help. Bet it will turn out beautifully!

Sure, why not! Mixing metals is very on trend.

If that is what you like go for it. The same applies to paint color. It is what brings a smile to your face that counts not what is trendy.