How do I bathroom / kitchen / extension? etc.

How hard would this be?

To delacquere brass ones? High risk imo.

I'd feel more comfortable buying chrome plated brass ones and fully stripping back to the brass. That way you'd know if you're getting an even finish.

I’ve done it many times to low value things - lacquered sash window pulls and latches etc. It depends on how they’re lacquered, and you can’t tell until you try. I have left in acetone, boiled in vinegar, cooked in oven to age, etc. and had good results, but I wasn’t looking for a particular finish, just to age them. I guess if you get markings you don’t like you can polish it again and let it tarnish naturally.