Without having clicked on every single link, I'll toss my hat in the ring for a Soma Buena Vista. Truly as modern of a mixte you are going to find. There are both rim and disc brake models and the sliding axle plates support a variety of standards combinations from OEM Rohloff, thru-axle, flat, and IS mount disk brakes in just about any combination you can think of if you know where to look.
I am so much pleased as punch with my Buena Vista built up as a road bike that I was inspired to build up another mixte from scratch configured with OEM Rohloff/flat mount sliders & the same Tange/IRD dropouts the Buena Vista uses. I accomplished this with Paragon Machine Works slider plates and Andrew Sutton Solutions IS to flat mount adaptors....Whatever. The point is the Buena Vista is a very versatile bike that can be configured in just about any way you want.
It would be hard to go wrong with the Soma.
Last edited by base2; 03-18-24 at 10:44 PM.