To add texture without adding a design through the backsplash. I am in the middle of kitchen remodel (basically the whole house) Farmhouse look

Agree photos would help. I think it depends on other elements in the kitchen, such as countertops, flooring and cabinets.

will post pics once counter top goes in

I love the matte/glossy mixes featured in Heath Tile website photos. Maybe if you reach out to them, they can offer good mix ratios.

It could possibly work in a stripe pattern for a very modern space, but I would stick with one or the other for a "farmhouse" look. You can get texture by using a contrasting grout, using handmade tiles, or textured tiles, but mixing glossy and matte would look like you ran out the the right tiles imo.

It will look great....

I would buy a box of each and do a dry layout and see what looks good to you

I think the mix of the two is quite nice. I could only find pics of color and darker greys but imagine white or light grey would look great given their subtlety, IMO. Not sure if I would do every other one as it might look too checker-like, but perhaps every two or more..or randomly scattered throughout.

If you don’t want a design stay with one tile the light will hit the gloss diffferent than the matte and it will still be a pattern which IMO is not worth the hassle a random apttern would be my choice but random is one of the hardest things to do

Some of the photos posted here show how you could have a pattern/design with some configurations. I'd want to ensure that would work with what you choose for the rest of the kitchen. For example, countertops with a defined pattern wouldn't work for me with the patterns shown in most of these photos.

I like the idea of mixing the 2 finishes. I'd opt for a random pattern for sure (like fuzzyguy posted). Also good advice to buy some of each tile and play around with the layout. Just make sure you have good communication with your tile person before the work starts :)