I would not do that style of blind and you have anice view why not just do simple solar shades outside mount on each window the double window is treated as one . The shades will control the heat and the UV let you keep the view and provide daytime privacty . I usually us drapes with them if night time privacy is an issue .

If that bllind on the single window is staying, then I think you need to match it on the double window. If you're replacing all of them, I could see doing either one blind or two on the double window. That shade header you show is huge, I'd look for something with a smaller header. I have inside mount Duette shades on all my windows and the header is the same width as the window casing so it doesn't stick out at all.

It doesn't look like the windows are recessed enough to do an inside mount without the header sticking out. I'd recommend an outside mount, and do one shade on the double windows. Two shades will be very narrow.

If you use that shade you’ll need to have 1 unit for the double window.

Your window locks and crank are going to interfere with the shade. It will clear those better and be less obvious with a single shade rather than 2 sitting at different angles.

I have the exact same locks and cranks on my windows and they do not interfere with the shade at all. Also, we are all assuming things about the size of your windows; what are their measurements? Width? How deep in the inside casing? Have you looked at other shades with a smaller header that would fit as an inside mount? Have you had someone come and consult with samples to show you what might work or not?

Just personal preference for me that inside mount gives a much cleaner/crisper look. But it depends on your style and what you're looking to achieve.

I also prefer inside mounted shades, but it's not always possible. The physical configuration can be limiting, as in this case.