Fake marble looks horrible with real marble, so it can't be any of that. Are you doing an envelope cut, to be able to use larger tile in the shower? Or does this need a mosaic for the floor.

If it were me, I wouldn't deal with marble on the walls either. I'd do every surface in Marble Attache Lavish, Diamond Carrarra. Gloss on the walls, the matte mosaic on the floors, and the matte field tile on the room floor. https://www.daltile.com/products/marble-look/marble-attache-lavish/diamond-carrara

For a tiny powder room, I would not tile the wallls. Just either paint or wall paper them.

I would go all porcelain. I sell a ton of tile from a company called Happy Floors. Take a look there!

I've decided natural stone is a must-have for the walls, but after reading a slew of reviews, I think ceramic or porcelain is the practical choice for the floors.

What's your rationale for thinking natural stone is necessary for the walls? Ceramic or porcelain is more practical -- won't stain or be ruined by the wrong cleaner. It's trouble. Do a search and see how many posts talk describe real marble "gone wrong".

Fake marble looks horrible with real marble, so it can't be any of that.

Right. No mixing.

hi thank you! I’m using full slabs in a shower room. I just do not like the look of quartz and porcelain leaves a seem. I wanted quartzite but was out of budget. I have about 12 ft by 6 ft of tile I need for the floor but can’t find anything that pairs well. i think mosaic or herringbone is what i‘m leaning towards. thanks again for the help!!

I use 12 x24 porcelain tile for both bathroom floor and shower walls they match they work wll and honestly there is no benefit to natura stone in a shower . I do not usually use fake look either just a nice simple neutral that is timeless and allows you to change other things down the road with no big expense. I like small spaces to have as few finishes as possible.