I think I'd use metal.

There's no indication of the style of the room from your photos, so here are some basic counter stools. Remember you cannot use bar stools...........too high.

I like kitchen stools to be a pop of color but that tile limits choices so maybe the blue you already have near this space

You could look at trying to do more muted stools so that you can add color with other pieces. You could do some simple black stools or metal stools and then add color and texture with wood and colored vases and pots.

Parisian Elegance · More Info

Modern Farmhouse Rebuild · More Info

You seem to be using that piece of art on the wall as inspiration for a color scheme for your open space. I love it! Go ahead and choose what you can find from that piece. That may be the determining factor... being able to find a stool in one of those colors. What do you think about one of the greyed teals?
Could the designer not incorporate the support post into your cabinet design? What a missed opportunity! https://vestabul.com/2022/01/18/how-to-integrate-posts-into-your-kitchen-designs/

And can you find an outlet plate that blends with the cabinet color? https://www.wallplates.com/