Not really the same but check out cement tile .They wear like iron and look good This one is from HD just google gray and white cement tile

All the most attractive waterjet designs use natural stone because waterjet time is expensive time. People will pay luxury prices for upscale waterjet cut natural stone, so the return on the outlay is there. Most won’t pay similar luxury prices for waterjet porcelain, which is why is is done less frequently. If you are willing to pay the costs for a one off luxury product, then there are many custom waterjet services available. Yes, it costs more than you think it costs inside your head as you hear ”custom waterjet cut porcelain”. But, if you have a local stone fabricator with a waterjet you might be able to convince them to branch out. It will take a LOT of legwork on your end to act as the designer for that, and properly liase between tile pro, stone pro, and material source. It all has to come together both technically and artistically. And be real world installable.

https://domusgroup.com/technical-solutions/waterjet-cut-designs

A possibility is to use a white ceramic/porcelain tile that matches the background of the marble on the floor and part way up the shower walls. Then use the marble on the upper shower walls out of the hard-wear zone. It would take some design planning to get the layout looking right, sort of how wainscoting has to be proportioned correctly to not look like a HGTV disaster. :)

Honestly if this is what you like best (it’s absolutely stunnasious!! Love it love it!! ) I might just bite the bullet and go with the marble 🫣 (I just don’t think you’ll get something so close to what you were looking for)

Here are some suggestions if you choose not to go that route :

https://www.bedrosians.com/en/product/detail/le-cafe-mosaic/?itemNo=100003615

Checkerboard tile

https://www.lowes.com/pd/Satori/5013913887?user=shopping&srsltid=AfmBOoqWXsCAla3tSRL_AG2mUwyILA2E9FxogsBNkCosu_Z1cU9ea-GF-8g&com_cvv=d30042528f072ba8a22b19c81250437cd47a2f30330f0ed03551c4efdaf3409e

https://www.tilebar.com/auteur-diagonals-ash-9x9-porcelain-tile-pattern-2.html