I've seen it for historical type renovations as it mimics a very traditional arts & crafts era tile, however the size is usually smaller like subway. Are you committed to the size that is shown there as well?

Possibly from fireclay. They make a 6 x 12 like that and it looks like their glazes.

Pratt & Larson has a Rustic field tile line that you can get in their watercolor or craftsman glazes, but the sizes are smaller, like a traditional 3x6 subway.

Example:

https://prattandlarson.com/product/rustic-4x8/ (this is a 3x6)

Iris tiles are also available in the US; may be not the same series. This is an example of one in our shop, it's 4x12.

Not as dark and not as green but there are glaze and texture to them:

https://www.wayfair.ca/home-improvement/pdp/ivy-hill-tile-oracle-3-x-6-ceramic-subway-tile-in-sky-sost3024.html

This one seems to have some unevenness unless they just play with colors to make it looks there is:

https://www.wayfair.ca/home-improvement/pdp/ivy-hill-tile-piston-industrial-glass-4-x-12-porcelain-subway-tile-in-white-sost2710.html

Others:

https://www.homedepot.com/p/Ivy-Hill-Tile-Oracle-Deep-Emerald-3-in-x-6-in-Polished-Ceramic-Subway-Tile-1-sq-ft-BRQ3X6CPRI/306742788

https://tilebar.com/castle-denim-3x12-ceramic-tile.html