The walls actually have to be built for the design with blocking in between the studs at key points. And preferably steel stud outs to slide the shelving over if you want it to support more than a coffee cup. No use in attempting this after the fact. And Id be scared of those cabinets staying up if you didn’t know you were dealing with steel. Train wreck here.

Wrong order of operations. It all had to be engineered while the walls were open. Not retrofittable at this point unless you can open up the space from the other side.

Sophie - highjacking this thread to ask you a question. I am also planning on installing some floating shelves in our kitchen. Not planned on holding anything significant weight...mostly decorative items and possible a few cookbooks. Our kitchen doesn't have a backsplash yet so anything is possible with minimal cost implications. I was thinking that we'd just have to locate the wood wall studs and drill the steel rods into those? Or are you saying that it's necessary to place wood blocking between the studs and drill into those?

Studs don’t always end up where you need them. Blocking does. And relying on any kind of drywall molly bolt for a floating shelf takes too big a risk for me.

For most “floating” shelves, I prefer to not use solid wood. It warps way too much. I prefer a cleat fastened into the studs and blocking, then you then “slipcover” the cleat with a plywood box. Solid edging if you want. But that will hold almost anything and have the strongest connection imaginable.

Sophie - thanks, that makes sense. Our floating shelves will be walnut 'slipcovers' so nothing solid. It will be easy enough for us to remove some sheetrock to do the blocking. It doesn't have to look pretty as it will eventually be covered with tile. I appreciate the expertise!